diff --git a/plugins/github-release-manager/src/GitHubReleaseManager.tsx b/plugins/github-release-manager/src/GitHubReleaseManager.tsx
index 3876d2b3fc..a52db523d4 100644
--- a/plugins/github-release-manager/src/GitHubReleaseManager.tsx
+++ b/plugins/github-release-manager/src/GitHubReleaseManager.tsx
@@ -81,11 +81,7 @@ export function GitHubReleaseManager({
   }
 
   return (
-    <PluginApiClientContext.Provider
-      value={
-        pluginApiClient as any // TODO: Fix type errors
-      }
-    >
+    <PluginApiClientContext.Provider value={pluginApiClient}>
       <div className={classes.root}>
         <ContentHeader title="GitHub Release Manager" />
 
@@ -119,7 +115,7 @@ function Cards({
   );
 
   const { versioningStrategyMatches } = useVersioningStrategyMatchesRepoTags({
-    latestReleaseTagName: gitHubBatchInfo.value?.latestRelease?.tag_name,
+    latestReleaseTagName: gitHubBatchInfo.value?.latestRelease?.tagName,
     project,
     repositoryName: gitHubBatchInfo.value?.repository.name,
   });
@@ -151,7 +147,7 @@ function Cards({
     return (
       <Alert severity="error">
         Versioning mismatch, expected {project.versioningStrategy} version, got{' '}
-        {gitHubBatchInfo.value?.latestRelease?.tag_name}
+        {gitHubBatchInfo.value.latestRelease?.tagName}
       </Alert>
     );
   }
diff --git a/plugins/github-release-manager/src/api/PluginApiClient.ts b/plugins/github-release-manager/src/api/PluginApiClient.ts
index 24310ef688..d348680cd1 100644
--- a/plugins/github-release-manager/src/api/PluginApiClient.ts
+++ b/plugins/github-release-manager/src/api/PluginApiClient.ts
@@ -19,10 +19,8 @@ import { Octokit } from '@octokit/rest';
 import { readGitHubIntegrationConfigs } from '@backstage/integration';
 
 import {
-  GhCompareCommitsResponse,
   GhCreateCommitResponse,
   GhCreateReferenceResponse,
-  GhCreateReleaseResponse,
   GhCreateTagObjectResponse,
   GhGetBranchResponse,
   GhGetCommitResponse,
@@ -36,32 +34,72 @@ import { getRcGitHubInfo } from '../cards/createRc/getRcGitHubInfo';
 import { SemverTagParts } from '../helpers/tagParts/getSemverTagParts';
 import { Project } from '../contexts/ProjectContext';
 
-// export type UnboxPromise<T extends Promise<any>> = T extends Promise<infer U>
-//   ? U
-//   : never;
+type UnboxPromise<T extends Promise<any>> = T extends Promise<infer U>
+  ? U
+  : never;
 
-type Todo = any;
+export type ApiMethodRetval<
+  T extends (...args: any) => Promise<any>
+> = UnboxPromise<ReturnType<T>>;
+
+type Todo = any; // TODO:
 type PartialProject = Omit<Project, 'versioningStrategy'>;
 
 export interface IPluginApiClient {
   getHost: () => string;
 
+  getRepoPath: (args: PartialProject) => string;
+
+  getOrganizations: () => Promise<{ organizations: string[] }>;
+
+  getRepositories: (args: {
+    owner: string;
+  }) => Promise<{ repositories: string[] }>;
+
+  getUsername: () => Promise<{ username: string }>;
+
   getRecentCommits: (
     args: { releaseBranchName?: string } & PartialProject,
-  ) => Promise<Todo>;
-  getReleases: (args: { releaseId: number } & PartialProject) => Promise<Todo>;
-  getRelease: (args: { releaseId: number } & PartialProject) => Promise<Todo>;
+  ) => Promise<{
+    recentCommits: {
+      sha: string;
+      author: {
+        htmlUrl?: string;
+        login?: string;
+      };
+      commit: {
+        message: string;
+      };
+    }[];
+  }>;
+
+  getLatestRelease: (
+    args: PartialProject,
+  ) => Promise<{
+    latestRelease: {
+      targetCommitish: string;
+      tagName: string;
+      prerelease: boolean;
+      id: number;
+      htmlUrl: string;
+      body?: string | null;
+    } | null;
+  }>;
+
   getRepository: (
     args: PartialProject,
   ) => Promise<{
     repository: {
       pushPermissions: boolean | undefined;
       defaultBranch: string;
+      name: string;
     };
   }>;
+
   getLatestCommit: (
     args: { defaultBranch: string } & PartialProject,
   ) => Promise<Todo>;
+
   getBranch: (args: { branchName: string } & PartialProject) => Promise<Todo>;
 
   createRc: {
@@ -70,21 +108,27 @@ export interface IPluginApiClient {
         mostRecentSha: string;
         targetBranch: string;
       } & PartialProject,
-    ) => Promise<Todo>;
+    ) => Promise<{ ref: string }>;
 
     getComparison: (
       args: {
         previousReleaseBranch: string;
         nextReleaseBranch: string;
       } & PartialProject,
-    ) => Promise<Todo>;
+    ) => Promise<{ htmlUrl: string; aheadBy: number }>;
 
     createRelease: (
       args: {
         nextGitHubInfo: ReturnType<typeof getRcGitHubInfo>;
         releaseBody: string;
       } & PartialProject,
-    ) => Promise<Todo>;
+    ) => Promise<{
+      createReleaseResponse: {
+        name: string | null;
+        htmlUrl: string;
+        tagName: string;
+      };
+    }>;
   };
 
   patch: {
@@ -142,7 +186,9 @@ export interface IPluginApiClient {
     updateRelease: (
       args: {
         bumpedTag: string;
-        latestRelease: GhGetReleaseResponse;
+        latestRelease: NonNullable<
+          ApiMethodRetval<IPluginApiClient['getLatestRelease']>['latestRelease']
+        >;
         tagParts: SemverTagParts | CalverTagParts;
         selectedPatchCommit: GhGetCommitResponse;
       } & PartialProject,
@@ -157,10 +203,6 @@ export interface IPluginApiClient {
       } & PartialProject,
     ) => Promise<Todo>;
   };
-
-  getOrganizations: (args: { ownerIsUser: boolean }) => Promise<Todo>;
-  getUsername: () => Promise<{ username: string }>;
-  getRepositories: (args: { owner: string; username: string }) => Promise<Todo>;
 }
 
 export class PluginApiClient implements IPluginApiClient {
@@ -221,36 +263,46 @@ export class PluginApiClient implements IPluginApiClient {
 
   async getOrganizations() {
     const { octokit } = await this.getOctokit();
-    const { data: orgs } = await octokit.orgs.listForAuthenticatedUser();
+    const orgListResponse = await octokit.paginate(
+      octokit.orgs.listForAuthenticatedUser,
+      { per_page: 100 },
+    );
 
-    return { orgs };
+    return {
+      organizations: orgListResponse.map(organization => organization.login),
+    };
   }
 
-  async getRepositories({
-    owner,
-    username,
-  }: {
-    owner: string;
-    username: string;
-  }) {
+  async getRepositories({ owner }: { owner: string }) {
     const { octokit } = await this.getOctokit();
 
-    if (owner === username) {
-      const { data: repos } = await octokit.repos.listForUser({ username });
+    const repositoryResponse = await octokit
+      .paginate(octokit.repos.listForOrg, { org: owner, per_page: 100 })
+      .catch(async error => {
+        // `owner` is not an org, try listing a user's repositories instead
+        if (error.status === 404) {
+          const userRepositoryResponse = await octokit.paginate(
+            octokit.repos.listForUser,
+            { username: owner, per_page: 100 },
+          );
+          return userRepositoryResponse;
+        }
 
-      return { repos };
-    }
+        throw error;
+      });
 
-    const { data: repos } = await octokit.repos.listForOrg({ org: owner });
-
-    return { repos };
+    return {
+      repositories: repositoryResponse.map(repository => repository.name),
+    };
   }
 
   async getUsername() {
     const { octokit } = await this.getOctokit();
-    const { data: user } = await octokit.users.getAuthenticated();
+    const userResponse = await octokit.users.getAuthenticated();
 
-    return { username: user.login };
+    return {
+      username: userResponse.data.login,
+    };
   }
 
   async getRecentCommits({
@@ -261,43 +313,52 @@ export class PluginApiClient implements IPluginApiClient {
     releaseBranchName?: string;
   } & PartialProject) {
     const { octokit } = await this.getOctokit();
-    const sha = releaseBranchName ? `?sha=${releaseBranchName}` : '';
+    const recentCommitsResponse = await octokit.repos.listCommits({
+      owner,
+      repo,
+      ...(releaseBranchName ? { sha: releaseBranchName } : {}),
+    });
 
-    const recentCommits: GhGetCommitResponse[] = (
-      await octokit.request(
-        `/repos/${this.getRepoPath({ owner, repo })}/commits${sha}`,
-      )
-    ).data;
-
-    return { recentCommits };
+    return {
+      recentCommits: recentCommitsResponse.data.map(commit => ({
+        sha: commit.sha,
+        author: {
+          htmlUrl: commit.author?.html_url,
+          login: commit.author?.login,
+        },
+        commit: {
+          message: commit.commit.message,
+        },
+      })),
+    };
   }
 
-  async getReleases({ owner, repo }: PartialProject) {
+  async getLatestRelease({ owner, repo }: PartialProject) {
     const { octokit } = await this.getOctokit();
+    const { data: latestReleases } = await octokit.repos.listReleases({
+      owner,
+      repo,
+      per_page: 1,
+    });
 
-    const releases: GhGetReleaseResponse[] = (
-      await octokit.request(
-        `/repos/${this.getRepoPath({ owner, repo })}/releases`,
-      )
-    ).data;
+    if (latestReleases.length === 0) {
+      return {
+        latestRelease: null,
+      };
+    }
 
-    return { releases };
-  }
+    const latestRelease = latestReleases[0];
 
-  async getRelease({
-    owner,
-    repo,
-    releaseId,
-  }: { releaseId: number } & PartialProject) {
-    const { octokit } = await this.getOctokit();
-
-    const latestRelease: GhGetReleaseResponse = (
-      await octokit.request(
-        `/repos/${this.getRepoPath({ owner, repo })}/releases/${releaseId}`,
-      )
-    ).data;
-
-    return { latestRelease };
+    return {
+      latestRelease: {
+        targetCommitish: latestRelease.target_commitish,
+        tagName: latestRelease.tag_name,
+        prerelease: latestRelease.prerelease,
+        id: latestRelease.id,
+        htmlUrl: latestRelease.html_url,
+        body: latestRelease.body,
+      },
+    };
   }
 
   async getRepository({ owner, repo }: PartialProject) {
@@ -363,21 +424,16 @@ export class PluginApiClient implements IPluginApiClient {
       targetBranch: string;
     } & PartialProject) => {
       const { octokit } = await this.getOctokit();
+      const createRefResponse = await octokit.git.createRef({
+        owner,
+        repo,
+        ref: `refs/heads/${targetBranch}`,
+        sha: mostRecentSha,
+      });
 
-      const createdRef: GhCreateReferenceResponse = (
-        await octokit.request(
-          `/repos/${this.getRepoPath({ owner, repo })}/git/refs`,
-          {
-            method: 'POST',
-            data: {
-              ref: `refs/heads/${targetBranch}`,
-              sha: mostRecentSha,
-            },
-          },
-        )
-      ).data;
-
-      return { createdRef };
+      return {
+        ref: createRefResponse.data.ref,
+      };
     },
 
     getComparison: async ({
@@ -390,17 +446,17 @@ export class PluginApiClient implements IPluginApiClient {
       nextReleaseBranch: string;
     } & PartialProject) => {
       const { octokit } = await this.getOctokit();
+      const compareCommitsResponse = await octokit.repos.compareCommits({
+        owner,
+        repo,
+        base: previousReleaseBranch,
+        head: nextReleaseBranch,
+      });
 
-      const comparison: GhCompareCommitsResponse = (
-        await octokit.request(
-          `/repos/${this.getRepoPath({
-            owner,
-            repo,
-          })}/compare/${previousReleaseBranch}...${nextReleaseBranch}`,
-        )
-      ).data;
-
-      return { comparison };
+      return {
+        htmlUrl: compareCommitsResponse.data.html_url,
+        aheadBy: compareCommitsResponse.data.ahead_by,
+      };
     },
 
     createRelease: async ({
@@ -413,24 +469,23 @@ export class PluginApiClient implements IPluginApiClient {
       releaseBody: string;
     } & PartialProject) => {
       const { octokit } = await this.getOctokit();
+      const createReleaseResponse = await octokit.repos.createRelease({
+        owner,
+        repo,
+        tag_name: nextGitHubInfo.rcReleaseTag,
+        name: nextGitHubInfo.releaseName,
+        target_commitish: nextGitHubInfo.rcBranch,
+        body: releaseBody,
+        prerelease: true,
+      });
 
-      const createReleaseResponse: GhCreateReleaseResponse = (
-        await octokit.request(
-          `/repos/${this.getRepoPath({ owner, repo })}/releases`,
-          {
-            method: 'POST',
-            data: {
-              tag_name: nextGitHubInfo.rcReleaseTag,
-              name: nextGitHubInfo.releaseName,
-              target_commitish: nextGitHubInfo.rcBranch,
-              body: releaseBody,
-              prerelease: true,
-            },
-          },
-        )
-      ).data;
-
-      return { createReleaseResponse };
+      return {
+        createReleaseResponse: {
+          name: createReleaseResponse.data.name,
+          htmlUrl: createReleaseResponse.data.html_url,
+          tagName: createReleaseResponse.data.tag_name,
+        },
+      };
     },
   };
 
@@ -640,7 +695,9 @@ export class PluginApiClient implements IPluginApiClient {
       selectedPatchCommit,
     }: {
       bumpedTag: string;
-      latestRelease: GhGetReleaseResponse;
+      latestRelease: NonNullable<
+        ApiMethodRetval<IPluginApiClient['getLatestRelease']>['latestRelease']
+      >;
       tagParts: SemverTagParts | CalverTagParts;
       selectedPatchCommit: GhGetCommitResponse;
     } & PartialProject) => {
diff --git a/plugins/github-release-manager/src/cards/createRc/CreateRc.tsx b/plugins/github-release-manager/src/cards/createRc/CreateRc.tsx
index 2f2fb6963b..b36478f082 100644
--- a/plugins/github-release-manager/src/cards/createRc/CreateRc.tsx
+++ b/plugins/github-release-manager/src/cards/createRc/CreateRc.tsx
@@ -33,7 +33,6 @@ import { InfoCardPlus } from '../../components/InfoCardPlus';
 import {
   ComponentConfigCreateRc,
   GhGetBranchResponse,
-  GhGetReleaseResponse,
   GhGetRepositoryResponse,
   SetRefetch,
 } from '../../types/types';
@@ -43,10 +42,13 @@ import { TEST_IDS } from '../../test-helpers/test-ids';
 import { usePluginApiClientContext } from '../../contexts/PluginApiClientContext';
 import { useProjectContext } from '../../contexts/ProjectContext';
 import { useStyles } from '../../styles/styles';
+import { ApiMethodRetval, IPluginApiClient } from '../../api/PluginApiClient';
 
 interface CreateRcProps {
   defaultBranch: GhGetRepositoryResponse['default_branch'];
-  latestRelease: GhGetReleaseResponse | null;
+  latestRelease: ApiMethodRetval<
+    IPluginApiClient['getLatestRelease']
+  >['latestRelease'];
   releaseBranch: GhGetBranchResponse | null;
   setRefetch: SetRefetch;
   successCb?: ComponentConfigCreateRc['successCb'];
@@ -97,7 +99,7 @@ export const CreateRc = ({
 
   const tagAlreadyExists =
     latestRelease !== null &&
-    latestRelease.tag_name === nextGitHubInfo.rcReleaseTag;
+    latestRelease.tagName === nextGitHubInfo.rcReleaseTag;
   const conflictingPreRelease =
     latestRelease !== null && latestRelease.prerelease;
 
@@ -132,7 +134,7 @@ export const CreateRc = ({
         <Typography>
           <Differ
             icon="tag"
-            prev={latestRelease?.tag_name}
+            prev={latestRelease?.tagName}
             next={nextGitHubInfo.rcReleaseTag}
           />
         </Typography>
diff --git a/plugins/github-release-manager/src/cards/createRc/getRcGitHubInfo.test.ts b/plugins/github-release-manager/src/cards/createRc/getRcGitHubInfo.test.ts
index 08eeacdcc9..31f9b6a4f4 100644
--- a/plugins/github-release-manager/src/cards/createRc/getRcGitHubInfo.test.ts
+++ b/plugins/github-release-manager/src/cards/createRc/getRcGitHubInfo.test.ts
@@ -16,7 +16,7 @@
 
 import { DateTime } from 'luxon';
 
-import { GhGetReleaseResponse } from '../../types/types';
+import { ApiMethodRetval, IPluginApiClient } from '../../api/PluginApiClient';
 import {
   mockSemverProject,
   mockCalverProject,
@@ -34,8 +34,8 @@ describe('getRcGitHubInfo', () => {
 
   describe('calver', () => {
     const latestRelease = {
-      tag_name: 'rc-2020.01.01_0',
-    } as GhGetReleaseResponse;
+      tagName: 'rc-2020.01.01_0',
+    } as ApiMethodRetval<IPluginApiClient['getLatestRelease']>['latestRelease'];
 
     it('should return correct GitHub info', () => {
       expect(
@@ -57,8 +57,8 @@ describe('getRcGitHubInfo', () => {
 
   describe('semver', () => {
     const latestRelease = {
-      tag_name: 'rc-1.1.1',
-    } as GhGetReleaseResponse;
+      tagName: 'rc-1.1.1',
+    } as ApiMethodRetval<IPluginApiClient['getLatestRelease']>['latestRelease'];
 
     it("should return correct GitHub info when there's previous releases", () => {
       expect(
diff --git a/plugins/github-release-manager/src/cards/createRc/getRcGitHubInfo.ts b/plugins/github-release-manager/src/cards/createRc/getRcGitHubInfo.ts
index cd2140296f..de70da6f9c 100644
--- a/plugins/github-release-manager/src/cards/createRc/getRcGitHubInfo.ts
+++ b/plugins/github-release-manager/src/cards/createRc/getRcGitHubInfo.ts
@@ -18,9 +18,9 @@ import { DateTime } from 'luxon';
 
 import { getBumpedSemverTagParts } from '../../helpers/getBumpedTag';
 import { getSemverTagParts } from '../../helpers/tagParts/getSemverTagParts';
-import { GhGetReleaseResponse } from '../../types/types';
 import { SEMVER_PARTS } from '../../constants/constants';
 import { Project } from '../../contexts/ProjectContext';
+import { ApiMethodRetval, IPluginApiClient } from '../../api/PluginApiClient';
 
 export const getRcGitHubInfo = ({
   project,
@@ -29,7 +29,9 @@ export const getRcGitHubInfo = ({
   injectedDate = DateTime.now().toFormat('yyyy.MM.dd'),
 }: {
   project: Project;
-  latestRelease: GhGetReleaseResponse | null;
+  latestRelease: ApiMethodRetval<
+    IPluginApiClient['getLatestRelease']
+  >['latestRelease'];
   semverBumpLevel: keyof typeof SEMVER_PARTS;
   injectedDate?: string;
 }) => {
@@ -49,7 +51,7 @@ export const getRcGitHubInfo = ({
     };
   }
 
-  const tagParts = getSemverTagParts(latestRelease.tag_name);
+  const tagParts = getSemverTagParts(latestRelease.tagName);
   const { bumpedTagParts } = getBumpedSemverTagParts(tagParts, semverBumpLevel);
 
   const bumpedTag = `${bumpedTagParts.major}.${bumpedTagParts.minor}.${bumpedTagParts.patch}`;
diff --git a/plugins/github-release-manager/src/cards/createRc/sideEffects/createRc.test.ts b/plugins/github-release-manager/src/cards/createRc/sideEffects/createRc.test.ts
index 9f75a6c927..e9ad6aca5a 100644
--- a/plugins/github-release-manager/src/cards/createRc/sideEffects/createRc.test.ts
+++ b/plugins/github-release-manager/src/cards/createRc/sideEffects/createRc.test.ts
@@ -28,10 +28,10 @@ describe('createRc', () => {
 
   it('should work', async () => {
     const result = await createRc({
-      pluginApiClient: mockApiClient,
       defaultBranch: mockDefaultBranch,
       latestRelease: mockReleaseVersion,
       nextGitHubInfo: mockNextGitHubInfo,
+      pluginApiClient: mockApiClient,
       project: mockCalverProject,
     });
 
diff --git a/plugins/github-release-manager/src/cards/createRc/sideEffects/createRc.ts b/plugins/github-release-manager/src/cards/createRc/sideEffects/createRc.ts
index 0f659fc994..c136f33cc2 100644
--- a/plugins/github-release-manager/src/cards/createRc/sideEffects/createRc.ts
+++ b/plugins/github-release-manager/src/cards/createRc/sideEffects/createRc.ts
@@ -17,20 +17,23 @@
 import { getRcGitHubInfo } from '../getRcGitHubInfo';
 import {
   ComponentConfigCreateRc,
-  GhCreateReferenceResponse,
-  GhGetReleaseResponse,
   GhGetRepositoryResponse,
   ResponseStep,
 } from '../../../types/types';
-import { PluginApiClient } from '../../../api/PluginApiClient';
+import {
+  ApiMethodRetval,
+  IPluginApiClient,
+} from '../../../api/PluginApiClient';
 import { GitHubReleaseManagerError } from '../../../errors/GitHubReleaseManagerError';
 import { Project } from '../../../contexts/ProjectContext';
 
 interface CreateRC {
   defaultBranch: GhGetRepositoryResponse['default_branch'];
-  latestRelease: GhGetReleaseResponse | null;
+  latestRelease: ApiMethodRetval<
+    IPluginApiClient['getLatestRelease']
+  >['latestRelease'];
   nextGitHubInfo: ReturnType<typeof getRcGitHubInfo>;
-  pluginApiClient: PluginApiClient;
+  pluginApiClient: IPluginApiClient;
   project: Project;
   successCb?: ComponentConfigCreateRc['successCb'];
 }
@@ -62,23 +65,20 @@ export async function createRc({
    * 2. Create a new ref based on the default branch's most recent sha
    */
   const mostRecentSha = latestCommit.sha;
-  let createdRef: GhCreateReferenceResponse;
-  try {
-    createdRef = (
-      await pluginApiClient.createRc.createRef({
-        ...project,
-        mostRecentSha,
-        targetBranch: nextGitHubInfo.rcBranch,
-      })
-    ).createdRef;
-  } catch (error) {
-    if (error.body.message === 'Reference already exists') {
-      throw new GitHubReleaseManagerError(
-        `Branch "${nextGitHubInfo.rcBranch}" already exists: .../tree/${nextGitHubInfo.rcBranch}`,
-      );
-    }
-    throw error;
-  }
+  const createdRef = await pluginApiClient.createRc
+    .createRef({
+      ...project,
+      mostRecentSha,
+      targetBranch: nextGitHubInfo.rcBranch,
+    })
+    .catch(error => {
+      if (error?.body?.message === 'Reference already exists') {
+        throw new GitHubReleaseManagerError(
+          `Branch "${nextGitHubInfo.rcBranch}" already exists: .../tree/${nextGitHubInfo.rcBranch}`,
+        );
+      }
+      throw error;
+    });
   responseSteps.push({
     message: 'Cut Release Branch',
     secondaryMessage: `with ref "${createdRef.ref}"`,
@@ -88,17 +88,17 @@ export async function createRc({
    * 3. Compose a body for the release
    */
   const previousReleaseBranch = latestRelease
-    ? latestRelease.target_commitish
+    ? latestRelease.targetCommitish
     : defaultBranch;
   const nextReleaseBranch = nextGitHubInfo.rcBranch;
-  const { comparison } = await pluginApiClient.createRc.getComparison({
+  const comparison = await pluginApiClient.createRc.getComparison({
     ...project,
     previousReleaseBranch,
     nextReleaseBranch,
   });
-  const releaseBody = `**Compare** ${comparison.html_url}
+  const releaseBody = `**Compare** ${comparison.htmlUrl}
 
-**Ahead by** ${comparison.ahead_by} commits
+**Ahead by** ${comparison.aheadBy} commits
 
 **Release branch** ${createdRef.ref}
 
@@ -108,7 +108,7 @@ export async function createRc({
   responseSteps.push({
     message: 'Fetched commit comparison',
     secondaryMessage: `${previousReleaseBranch}...${nextReleaseBranch}`,
-    link: comparison.html_url,
+    link: comparison.htmlUrl,
   });
 
   /**
@@ -124,15 +124,15 @@ export async function createRc({
   responseSteps.push({
     message: `Created Release Candidate "${createReleaseResponse.name}"`,
     secondaryMessage: `with tag "${nextGitHubInfo.rcReleaseTag}"`,
-    link: createReleaseResponse.html_url,
+    link: createReleaseResponse.htmlUrl,
   });
 
   await successCb?.({
-    gitHubReleaseUrl: createReleaseResponse.html_url,
+    gitHubReleaseUrl: createReleaseResponse.htmlUrl,
     gitHubReleaseName: createReleaseResponse.name,
-    comparisonUrl: comparison.html_url,
-    previousTag: latestRelease?.tag_name,
-    createdTag: createReleaseResponse.tag_name,
+    comparisonUrl: comparison.htmlUrl,
+    previousTag: latestRelease?.tagName,
+    createdTag: createReleaseResponse.tagName,
   });
 
   return responseSteps;
diff --git a/plugins/github-release-manager/src/cards/info/Info.tsx b/plugins/github-release-manager/src/cards/info/Info.tsx
index 1f42c5b603..782ed30460 100644
--- a/plugins/github-release-manager/src/cards/info/Info.tsx
+++ b/plugins/github-release-manager/src/cards/info/Info.tsx
@@ -18,20 +18,24 @@ import React from 'react';
 import { Link, Typography } from '@material-ui/core';
 
 import { Differ } from '../../components/Differ';
-import { GhGetBranchResponse, GhGetReleaseResponse } from '../../types/types';
+import { GhGetBranchResponse } from '../../types/types';
 import { InfoCardPlus } from '../../components/InfoCardPlus';
 import { TEST_IDS } from '../../test-helpers/test-ids';
 import { useProjectContext } from '../../contexts/ProjectContext';
 import { useStyles } from '../../styles/styles';
 import flowImage from './flow.png';
+import { ApiMethodRetval, IPluginApiClient } from '../../api/PluginApiClient';
 
 interface InfoCardProps {
   releaseBranch: GhGetBranchResponse | null;
-  latestRelease: GhGetReleaseResponse | null;
+  latestRelease: ApiMethodRetval<
+    IPluginApiClient['getLatestRelease']
+  >['latestRelease'];
 }
 
 export const Info = ({ releaseBranch, latestRelease }: InfoCardProps) => {
   const project = useProjectContext();
+
   const classes = useStyles();
 
   return (
@@ -98,7 +102,7 @@ export const Info = ({ releaseBranch, latestRelease }: InfoCardProps) => {
         </Typography>
 
         <Typography>
-          Latest release: <Differ icon="tag" next={latestRelease?.tag_name} />
+          Latest release: <Differ icon="tag" next={latestRelease?.tagName} />
         </Typography>
       </div>
     </InfoCardPlus>
diff --git a/plugins/github-release-manager/src/cards/patchRc/Patch.tsx b/plugins/github-release-manager/src/cards/patchRc/Patch.tsx
index e0c1be7a24..e19287024c 100644
--- a/plugins/github-release-manager/src/cards/patchRc/Patch.tsx
+++ b/plugins/github-release-manager/src/cards/patchRc/Patch.tsx
@@ -23,15 +23,17 @@ import { NoLatestRelease } from '../../components/NoLatestRelease';
 import {
   ComponentConfigPatch,
   GhGetBranchResponse,
-  GhGetReleaseResponse,
   SetRefetch,
 } from '../../types/types';
 import { PatchBody } from './PatchBody';
 import { useProjectContext } from '../../contexts/ProjectContext';
 import { useStyles } from '../../styles/styles';
+import { ApiMethodRetval, IPluginApiClient } from '../../api/PluginApiClient';
 
 interface PatchProps {
-  latestRelease: GhGetReleaseResponse | null;
+  latestRelease: ApiMethodRetval<
+    IPluginApiClient['getLatestRelease']
+  >['latestRelease'];
   releaseBranch: GhGetBranchResponse | null;
   setRefetch: SetRefetch;
   successCb?: ComponentConfigPatch['successCb'];
@@ -53,7 +55,7 @@ export const Patch = ({
 
     const { bumpedTag, tagParts } = getBumpedTag({
       project,
-      tag: latestRelease.tag_name,
+      tag: latestRelease.tagName,
       bumpLevel: 'patch',
     });
 
diff --git a/plugins/github-release-manager/src/cards/patchRc/PatchBody.test.tsx b/plugins/github-release-manager/src/cards/patchRc/PatchBody.test.tsx
index 5c208e9955..54daf2894f 100644
--- a/plugins/github-release-manager/src/cards/patchRc/PatchBody.test.tsx
+++ b/plugins/github-release-manager/src/cards/patchRc/PatchBody.test.tsx
@@ -41,7 +41,7 @@ describe('PatchBody', () => {
   beforeEach(jest.clearAllMocks);
 
   it('should render error', async () => {
-    mockApiClient.getBranch.mockImplementationOnce(() => {
+    (mockApiClient.getBranch as jest.Mock).mockImplementationOnce(() => {
       throw new Error('banana');
     });
 
diff --git a/plugins/github-release-manager/src/cards/patchRc/PatchBody.tsx b/plugins/github-release-manager/src/cards/patchRc/PatchBody.tsx
index 40582dbc0f..44907d30f1 100644
--- a/plugins/github-release-manager/src/cards/patchRc/PatchBody.tsx
+++ b/plugins/github-release-manager/src/cards/patchRc/PatchBody.tsx
@@ -38,7 +38,6 @@ import {
   ComponentConfigPatch,
   GhGetBranchResponse,
   GhGetCommitResponse,
-  GhGetReleaseResponse,
   SetRefetch,
 } from '../../types/types';
 import { CalverTagParts } from '../../helpers/tagParts/getCalverTagParts';
@@ -50,10 +49,13 @@ import { TEST_IDS } from '../../test-helpers/test-ids';
 import { usePluginApiClientContext } from '../../contexts/PluginApiClientContext';
 import { useProjectContext } from '../../contexts/ProjectContext';
 import { useStyles } from '../../styles/styles';
+import { ApiMethodRetval, IPluginApiClient } from '../../api/PluginApiClient';
 
 interface PatchBodyProps {
   bumpedTag: string;
-  latestRelease: GhGetReleaseResponse;
+  latestRelease: NonNullable<
+    ApiMethodRetval<IPluginApiClient['getLatestRelease']>['latestRelease']
+  >;
   releaseBranch: GhGetBranchResponse | null;
   setRefetch: SetRefetch;
   successCb?: ComponentConfigPatch['successCb'];
@@ -75,17 +77,17 @@ export const PatchBody = ({
   const githubDataResponse = useAsync(async () => {
     const [
       { branch: releaseBranchResponse },
-      { recentCommits },
+      { recentCommits: recentCommitsOnDefaultBranch },
     ] = await Promise.all([
       pluginApiClient.getBranch({
         ...project,
-        branchName: latestRelease.target_commitish,
+        branchName: latestRelease.targetCommitish,
       }),
       pluginApiClient.getRecentCommits({ ...project }),
     ]);
 
     const {
-      recentCommits: recentReleaseBranchCommits,
+      recentCommits: recentCommitsOnReleaseBranch,
     } = await pluginApiClient.getRecentCommits({
       ...project,
       releaseBranchName: releaseBranchResponse.name,
@@ -93,8 +95,8 @@ export const PatchBody = ({
 
     return {
       releaseBranch: releaseBranchResponse,
-      recentReleaseBranchCommits,
-      recentCommits,
+      recentCommitsOnReleaseBranch,
+      recentCommitsOnDefaultBranch,
     };
   });
 
@@ -146,118 +148,118 @@ export const PatchBody = ({
         )}
 
         <Typography className={classes.paragraph}>
-          <Differ icon="tag" prev={latestRelease.tag_name} next={bumpedTag} />
+          <Differ icon="tag" prev={latestRelease.tagName} next={bumpedTag} />
         </Typography>
       </>
     );
   }
 
   function CommitList() {
-    if (!githubDataResponse.value?.recentCommits) {
+    if (!githubDataResponse.value?.recentCommitsOnDefaultBranch) {
       return null;
     }
 
     return (
       <List>
-        {githubDataResponse.value.recentCommits.map((commit, index) => {
-          const commitExistsOnReleaseBranch = !!githubDataResponse.value?.recentReleaseBranchCommits.find(
-            ({ sha }) => {
-              return sha === commit.sha;
-            },
-          );
+        {githubDataResponse.value.recentCommitsOnDefaultBranch.map(
+          (commit, index) => {
+            const commitExistsOnReleaseBranch = !!githubDataResponse.value?.recentCommitsOnReleaseBranch.find(
+              releaseBranchCommit => releaseBranchCommit.sha === commit.sha,
+            );
 
-          return (
-            <div style={{ position: 'relative' }} key={`commit-${index}`}>
-              {commitExistsOnReleaseBranch && (
-                <Paper
-                  elevation={3}
-                  style={{
-                    position: 'absolute',
-                    top: '50%',
-                    left: '50%',
-                    transform: 'translate3d(-50%,-50%,0)',
-                    zIndex: 10,
-                    color: 'green',
-                    padding: 6,
-                    background: 'rgba(244,244,244,1)',
-                    borderRadius: 8,
-                  }}
-                >
-                  <FileCopyIcon
-                    fontSize="small"
-                    style={{ verticalAlign: 'middle' }}
-                  />{' '}
-                  Already exists on <b>{releaseBranch?.name}</b>
-                </Paper>
-              )}
-
-              <ListItem
-                disabled={
-                  patchReleaseResponse.loading ||
-                  (patchReleaseResponse.value &&
-                    patchReleaseResponse.value.length > 0) ||
-                  commitExistsOnReleaseBranch
-                }
-                role={undefined}
-                dense
-                button
-                onClick={() => {
-                  if (index === checkedCommitIndex) {
-                    setCheckedCommitIndex(-1);
-                  } else {
-                    setCheckedCommitIndex(index);
-                  }
-                }}
-              >
-                <ListItemIcon>
-                  <Checkbox
-                    edge="start"
-                    checked={checkedCommitIndex === index}
-                    tabIndex={-1}
-                  />
-                </ListItemIcon>
-
-                <ListItemText
-                  id={commit.sha}
-                  primary={commit.commit.message}
-                  secondary={
-                    <>
-                      {commit.sha}{' '}
-                      <Link
-                        color="primary"
-                        href={commit.author.html_url}
-                        target="_blank"
-                      >
-                        @{commit.author.login}
-                      </Link>
-                    </>
-                  }
-                />
-
-                <ListItemSecondaryAction>
-                  <IconButton
-                    aria-label="commit"
-                    disabled={commitExistsOnReleaseBranch || !releaseBranch}
-                    onClick={() => {
-                      const repoPath = pluginApiClient.getRepoPath({
-                        ...project,
-                      });
-                      const host = pluginApiClient.getHost();
-
-                      const newTab = window.open(
-                        `https://${host}/${repoPath}/compare/${releaseBranch?.name}...${commit.sha}`,
-                        '_blank',
-                      );
-                      newTab?.focus();
+            return (
+              <div style={{ position: 'relative' }} key={`commit-${index}`}>
+                {commitExistsOnReleaseBranch && (
+                  <Paper
+                    elevation={3}
+                    style={{
+                      position: 'absolute',
+                      top: '50%',
+                      left: '50%',
+                      transform: 'translate3d(-50%,-50%,0)',
+                      zIndex: 10,
+                      color: 'green',
+                      padding: 6,
+                      background: 'rgba(244,244,244,1)',
+                      borderRadius: 8,
                     }}
                   >
-                    <OpenInNewIcon />
-                  </IconButton>
-                </ListItemSecondaryAction>
-              </ListItem>
-            </div>
-          );
-        })}
+                    <FileCopyIcon
+                      fontSize="small"
+                      style={{ verticalAlign: 'middle' }}
+                    />{' '}
+                    Already exists on <b>{releaseBranch?.name}</b>
+                  </Paper>
+                )}
+
+                <ListItem
+                  disabled={
+                    patchReleaseResponse.loading ||
+                    (patchReleaseResponse.value &&
+                      patchReleaseResponse.value.length > 0) ||
+                    commitExistsOnReleaseBranch
+                  }
+                  role={undefined}
+                  dense
+                  button
+                  onClick={() => {
+                    if (index === checkedCommitIndex) {
+                      setCheckedCommitIndex(-1);
+                    } else {
+                      setCheckedCommitIndex(index);
+                    }
+                  }}
+                >
+                  <ListItemIcon>
+                    <Checkbox
+                      edge="start"
+                      checked={checkedCommitIndex === index}
+                      tabIndex={-1}
+                    />
+                  </ListItemIcon>
+
+                  <ListItemText
+                    id={commit.sha}
+                    primary={commit.commit.message}
+                    secondary={
+                      <>
+                        {commit.sha}{' '}
+                        <Link
+                          color="primary"
+                          href={commit.author.htmlUrl}
+                          target="_blank"
+                        >
+                          @{commit.author.login}
+                        </Link>
+                      </>
+                    }
+                  />
+
+                  <ListItemSecondaryAction>
+                    <IconButton
+                      aria-label="commit"
+                      disabled={commitExistsOnReleaseBranch || !releaseBranch}
+                      onClick={() => {
+                        const repoPath = pluginApiClient.getRepoPath({
+                          ...project,
+                        });
+                        const host = pluginApiClient.getHost();
+
+                        const newTab = window.open(
+                          `https://${host}/${repoPath}/compare/${releaseBranch?.name}...${commit.sha}`,
+                          '_blank',
+                        );
+                        newTab?.focus();
+                      }}
+                    >
+                      <OpenInNewIcon />
+                    </IconButton>
+                  </ListItemSecondaryAction>
+                </ListItem>
+              </div>
+            );
+          },
+        )}
       </List>
     );
   }
@@ -275,7 +277,11 @@ export const PatchBody = ({
       );
     }
 
-    if (!githubDataResponse.value?.recentCommits[checkedCommitIndex]) {
+    if (
+      !githubDataResponse.value?.recentCommitsOnDefaultBranch[
+        checkedCommitIndex
+      ]
+    ) {
       return (
         <Button disabled variant="contained" color="primary">
           Patch Release Candidate
@@ -291,7 +297,9 @@ export const PatchBody = ({
         onClick={() => {
           // FIXME: Optional chaining shouldn't be needed here due to the if-statement above
           patchReleaseFn(
-            githubDataResponse.value?.recentCommits[checkedCommitIndex],
+            githubDataResponse.value?.recentCommitsOnDefaultBranch[
+              checkedCommitIndex
+            ],
           );
         }}
       >
diff --git a/plugins/github-release-manager/src/cards/patchRc/sideEffects/patch.ts b/plugins/github-release-manager/src/cards/patchRc/sideEffects/patch.ts
index 7bb0d5e6f0..b2c226c51c 100644
--- a/plugins/github-release-manager/src/cards/patchRc/sideEffects/patch.ts
+++ b/plugins/github-release-manager/src/cards/patchRc/sideEffects/patch.ts
@@ -17,19 +17,23 @@
 import {
   ComponentConfigPatch,
   GhGetCommitResponse,
-  GhGetReleaseResponse,
   ResponseStep,
 } from '../../../types/types';
 import { CalverTagParts } from '../../../helpers/tagParts/getCalverTagParts';
 import { GitHubReleaseManagerError } from '../../../errors/GitHubReleaseManagerError';
-import { PluginApiClient } from '../../../api/PluginApiClient';
+import {
+  ApiMethodRetval,
+  IPluginApiClient,
+} from '../../../api/PluginApiClient';
 import { Project } from '../../../contexts/ProjectContext';
 import { SemverTagParts } from '../../../helpers/tagParts/getSemverTagParts';
 
 interface Patch {
   bumpedTag: string;
-  latestRelease: GhGetReleaseResponse;
-  pluginApiClient: PluginApiClient;
+  latestRelease: NonNullable<
+    ApiMethodRetval<IPluginApiClient['getLatestRelease']>['latestRelease']
+  >;
+  pluginApiClient: IPluginApiClient;
   project: Project;
   selectedPatchCommit: GhGetCommitResponse;
   successCb?: ComponentConfigPatch['successCb'];
@@ -52,7 +56,7 @@ export async function patch({
     throw new GitHubReleaseManagerError('Invalid commit');
   }
 
-  const releaseBranchName = latestRelease.target_commitish;
+  const releaseBranchName = latestRelease.targetCommitish;
   /**
    * 1. Here is the branch we want to cherry-pick to:
    * > branch = GET /repos/$owner/$repo/branches/$branchName
@@ -199,7 +203,7 @@ export async function patch({
   await successCb?.({
     updatedReleaseUrl: updatedRelease.html_url,
     updatedReleaseName: updatedRelease.name,
-    previousTag: latestRelease.tag_name,
+    previousTag: latestRelease.tagName,
     patchedTag: updatedRelease.tag_name,
     patchCommitUrl: selectedPatchCommit.html_url,
     patchCommitMessage: selectedPatchCommit.commit.message,
diff --git a/plugins/github-release-manager/src/cards/projectForm/Owner.tsx b/plugins/github-release-manager/src/cards/projectForm/Owner.tsx
index f95d66159f..aa56e72db4 100644
--- a/plugins/github-release-manager/src/cards/projectForm/Owner.tsx
+++ b/plugins/github-release-manager/src/cards/projectForm/Owner.tsx
@@ -48,7 +48,7 @@ export function Owner({
     return <CenteredCircularProgress />;
   }
 
-  if (!value?.orgs) {
+  if (!value?.organizations) {
     return <Alert severity="error">Could not fetch organizations</Alert>;
   }
 
@@ -74,9 +74,9 @@ export function Owner({
         <MenuItem value={username}>
           <strong>{username}</strong>
         </MenuItem>
-        {value.orgs.map((org, index) => (
-          <MenuItem key={`organization-${index}`} value={org.login}>
-            {org.login}
+        {value.organizations.map((orgName, index) => (
+          <MenuItem key={`organization-${index}`} value={orgName}>
+            {orgName}
           </MenuItem>
         ))}
       </Select>
diff --git a/plugins/github-release-manager/src/cards/projectForm/Repo.tsx b/plugins/github-release-manager/src/cards/projectForm/Repo.tsx
index 9c83c30565..8e24081c60 100644
--- a/plugins/github-release-manager/src/cards/projectForm/Repo.tsx
+++ b/plugins/github-release-manager/src/cards/projectForm/Repo.tsx
@@ -18,7 +18,7 @@ import React from 'react';
 import { useAsync } from 'react-use';
 import { FormControl, InputLabel, Select, MenuItem } from '@material-ui/core';
 import { Alert } from '@material-ui/lab';
-import { ControllerRenderProps, useForm } from 'react-hook-form';
+import { ControllerRenderProps } from 'react-hook-form';
 
 import { usePluginApiClientContext } from '../../contexts/PluginApiClientContext';
 import { useFormClasses } from './styles';
@@ -26,10 +26,8 @@ import { CenteredCircularProgress } from '../../components/CenteredCircularProgr
 import { Project } from '../../contexts/ProjectContext';
 
 export function Repo({
-  username,
   controllerRenderProps,
 }: {
-  username: string;
   controllerRenderProps: ControllerRenderProps;
 }) {
   const pluginApiClient = usePluginApiClientContext();
@@ -37,11 +35,7 @@ export function Repo({
   const project: Project = controllerRenderProps.value;
 
   const { loading, error, value } = useAsync(
-    () =>
-      pluginApiClient.getRepositories({
-        owner: project.owner,
-        username,
-      }),
+    async () => pluginApiClient.getRepositories({ owner: project.owner }),
     [project.owner],
   );
 
@@ -53,7 +47,7 @@ export function Repo({
     return <CenteredCircularProgress />;
   }
 
-  if (!value?.repos) {
+  if (!value?.repositories) {
     return (
       <Alert severity="error">
         Could not fetch repositories for "{project.owner}"
@@ -79,9 +73,9 @@ export function Repo({
         <MenuItem value="">
           <em>None</em>
         </MenuItem>
-        {value.repos.map((repository, index) => (
-          <MenuItem key={`repository-${index}`} value={repository.name}>
-            {repository.name}
+        {value.repositories.map((repositoryName, index) => (
+          <MenuItem key={`repository-${index}`} value={repositoryName}>
+            {repositoryName}
           </MenuItem>
         ))}
       </Select>
diff --git a/plugins/github-release-manager/src/cards/projectForm/RepoDetailsForm.tsx b/plugins/github-release-manager/src/cards/projectForm/RepoDetailsForm.tsx
index 03996b484d..2ba5f457a1 100644
--- a/plugins/github-release-manager/src/cards/projectForm/RepoDetailsForm.tsx
+++ b/plugins/github-release-manager/src/cards/projectForm/RepoDetailsForm.tsx
@@ -44,10 +44,7 @@ export function RepoDetailsForm({
             />
 
             {project.owner.length > 0 && (
-              <Repo
-                controllerRenderProps={controllerRenderProps}
-                username={username}
-              />
+              <Repo controllerRenderProps={controllerRenderProps} />
             )}
           </>
         );
diff --git a/plugins/github-release-manager/src/cards/promoteRc/PromoteRc.tsx b/plugins/github-release-manager/src/cards/promoteRc/PromoteRc.tsx
index d30271be48..4ca8b06fa6 100644
--- a/plugins/github-release-manager/src/cards/promoteRc/PromoteRc.tsx
+++ b/plugins/github-release-manager/src/cards/promoteRc/PromoteRc.tsx
@@ -20,17 +20,16 @@ import { Typography } from '@material-ui/core';
 
 import { InfoCardPlus } from '../../components/InfoCardPlus';
 import { NoLatestRelease } from '../../components/NoLatestRelease';
-import {
-  ComponentConfigPromoteRc,
-  GhGetReleaseResponse,
-  SetRefetch,
-} from '../../types/types';
+import { ComponentConfigPromoteRc, SetRefetch } from '../../types/types';
 import { PromoteRcBody } from './PromoteRcBody';
 import { useStyles } from '../../styles/styles';
 import { TEST_IDS } from '../../test-helpers/test-ids';
+import { ApiMethodRetval, IPluginApiClient } from '../../api/PluginApiClient';
 
 interface PromoteRcProps {
-  latestRelease: GhGetReleaseResponse | null;
+  latestRelease: ApiMethodRetval<
+    IPluginApiClient['getLatestRelease']
+  >['latestRelease'];
   setRefetch: SetRefetch;
   successCb?: ComponentConfigPromoteRc['successCb'];
 }
diff --git a/plugins/github-release-manager/src/cards/promoteRc/PromoteRcBody.tsx b/plugins/github-release-manager/src/cards/promoteRc/PromoteRcBody.tsx
index 7b20845c92..d55768e45a 100644
--- a/plugins/github-release-manager/src/cards/promoteRc/PromoteRcBody.tsx
+++ b/plugins/github-release-manager/src/cards/promoteRc/PromoteRcBody.tsx
@@ -20,20 +20,19 @@ import { Alert } from '@material-ui/lab';
 import { Button, Typography } from '@material-ui/core';
 
 import { Differ } from '../../components/Differ';
-import {
-  ComponentConfigPromoteRc,
-  GhGetReleaseResponse,
-  SetRefetch,
-} from '../../types/types';
+import { ComponentConfigPromoteRc, SetRefetch } from '../../types/types';
 import { promoteRc } from './sideEffects/promoteRc';
 import { ResponseStepList } from '../../components/ResponseStepList/ResponseStepList';
 import { TEST_IDS } from '../../test-helpers/test-ids';
 import { usePluginApiClientContext } from '../../contexts/PluginApiClientContext';
 import { useProjectContext } from '../../contexts/ProjectContext';
 import { useStyles } from '../../styles/styles';
+import { ApiMethodRetval, IPluginApiClient } from '../../api/PluginApiClient';
 
 interface PromoteRcBodyProps {
-  rcRelease: GhGetReleaseResponse;
+  rcRelease: NonNullable<
+    ApiMethodRetval<IPluginApiClient['getLatestRelease']>['latestRelease']
+  >;
   setRefetch: SetRefetch;
   successCb?: ComponentConfigPromoteRc['successCb'];
 }
@@ -46,7 +45,7 @@ export const PromoteRcBody = ({
   const pluginApiClient = usePluginApiClientContext();
   const project = useProjectContext();
   const classes = useStyles();
-  const releaseVersion = rcRelease.tag_name.replace('rc-', 'version-');
+  const releaseVersion = rcRelease.tagName.replace('rc-', 'version-');
   const [promoteGitHubRcResponse, promoseGitHubRcFn] = useAsyncFn(
     promoteRc({
       pluginApiClient,
@@ -71,7 +70,7 @@ export const PromoteRcBody = ({
         </Typography>
 
         <Typography className={classes.paragraph}>
-          <Differ icon="tag" prev={rcRelease.tag_name} next={releaseVersion} />
+          <Differ icon="tag" prev={rcRelease.tagName} next={releaseVersion} />
         </Typography>
       </>
     );
diff --git a/plugins/github-release-manager/src/cards/promoteRc/sideEffects/promoteRc.test.ts b/plugins/github-release-manager/src/cards/promoteRc/sideEffects/promoteRc.test.ts
index e57ccd5898..3bd3ceab90 100644
--- a/plugins/github-release-manager/src/cards/promoteRc/sideEffects/promoteRc.test.ts
+++ b/plugins/github-release-manager/src/cards/promoteRc/sideEffects/promoteRc.test.ts
@@ -15,8 +15,9 @@
  */
 
 import {
-  mockRcRelease,
   mockApiClient,
+  mockRcRelease,
+  mockSemverProject,
 } from '../../../test-helpers/test-helpers';
 import { promoteRc } from './promoteRc';
 
@@ -28,6 +29,7 @@ describe('promoteRc', () => {
       pluginApiClient: mockApiClient,
       rcRelease: mockRcRelease,
       releaseVersion: 'version-1.2.3',
+      project: mockSemverProject,
     })();
 
     expect(result).toMatchInlineSnapshot(`
diff --git a/plugins/github-release-manager/src/cards/promoteRc/sideEffects/promoteRc.ts b/plugins/github-release-manager/src/cards/promoteRc/sideEffects/promoteRc.ts
index 0d38b53fba..4a254ca2a9 100644
--- a/plugins/github-release-manager/src/cards/promoteRc/sideEffects/promoteRc.ts
+++ b/plugins/github-release-manager/src/cards/promoteRc/sideEffects/promoteRc.ts
@@ -14,18 +14,19 @@
  * limitations under the License.
  */
 
+import { ComponentConfigPromoteRc, ResponseStep } from '../../../types/types';
 import {
-  ComponentConfigPromoteRc,
-  GhGetReleaseResponse,
-  ResponseStep,
-} from '../../../types/types';
-import { PluginApiClient } from '../../../api/PluginApiClient';
+  ApiMethodRetval,
+  IPluginApiClient,
+} from '../../../api/PluginApiClient';
 import { Project } from '../../../contexts/ProjectContext';
 
 interface PromoteRc {
-  pluginApiClient: PluginApiClient;
+  pluginApiClient: IPluginApiClient;
   project: Project;
-  rcRelease: GhGetReleaseResponse;
+  rcRelease: NonNullable<
+    ApiMethodRetval<IPluginApiClient['getLatestRelease']>['latestRelease']
+  >;
   releaseVersion: string;
   successCb?: ComponentConfigPromoteRc['successCb'];
 }
@@ -47,15 +48,15 @@ export function promoteRc({
     });
     responseSteps.push({
       message: `Promoted "${release.name}"`,
-      secondaryMessage: `from "${rcRelease.tag_name}" to "${release.tag_name}"`,
+      secondaryMessage: `from "${rcRelease.tagName}" to "${release.tag_name}"`,
       link: release.html_url,
     });
 
     await successCb?.({
       gitHubReleaseUrl: release.html_url,
       gitHubReleaseName: release.name,
-      previousTagUrl: rcRelease.html_url,
-      previousTag: rcRelease.tag_name,
+      previousTagUrl: rcRelease.htmlUrl,
+      previousTag: rcRelease.tagName,
       updatedTagUrl: release.html_url,
       updatedTag: release.tag_name,
     });
diff --git a/plugins/github-release-manager/src/contexts/PluginApiClientContext.ts b/plugins/github-release-manager/src/contexts/PluginApiClientContext.ts
index 6417d7bdf5..1954321644 100644
--- a/plugins/github-release-manager/src/contexts/PluginApiClientContext.ts
+++ b/plugins/github-release-manager/src/contexts/PluginApiClientContext.ts
@@ -16,11 +16,11 @@
 
 import { createContext, useContext } from 'react';
 
-import { PluginApiClient } from '../api/PluginApiClient';
+import { IPluginApiClient } from '../api/PluginApiClient';
 import { GitHubReleaseManagerError } from '../errors/GitHubReleaseManagerError';
 
 export const PluginApiClientContext = createContext<
-  PluginApiClient | undefined
+  IPluginApiClient | undefined
 >(undefined);
 
 export const usePluginApiClientContext = () => {
diff --git a/plugins/github-release-manager/src/helpers/isCalverTagParts.ts b/plugins/github-release-manager/src/helpers/isCalverTagParts.ts
index dbc373a5aa..5e6d8cfa9c 100644
--- a/plugins/github-release-manager/src/helpers/isCalverTagParts.ts
+++ b/plugins/github-release-manager/src/helpers/isCalverTagParts.ts
@@ -14,8 +14,8 @@
  * limitations under the License.
  */
 
+import { Project } from '../contexts/ProjectContext';
 import { CalverTagParts } from './tagParts/getCalverTagParts';
-import { Project } from '../types/types';
 
 export function isCalverTagParts(
   project: Project,
diff --git a/plugins/github-release-manager/src/sideEffects/getGitHubBatchInfo.ts b/plugins/github-release-manager/src/sideEffects/getGitHubBatchInfo.ts
index 8a1bec9165..2b00f0e84b 100644
--- a/plugins/github-release-manager/src/sideEffects/getGitHubBatchInfo.ts
+++ b/plugins/github-release-manager/src/sideEffects/getGitHubBatchInfo.ts
@@ -14,22 +14,21 @@
  * limitations under the License.
  */
 
-import { getLatestRelease } from './getLatestRelease';
-import { PluginApiClient } from '../api/PluginApiClient';
+import { IPluginApiClient } from '../api/PluginApiClient';
 import { Project } from '../contexts/ProjectContext';
 
 interface GetGitHubBatchInfo {
   project: Project;
-  pluginApiClient: PluginApiClient;
+  pluginApiClient: IPluginApiClient;
 }
 
 export const getGitHubBatchInfo = ({
   project,
   pluginApiClient,
 }: GetGitHubBatchInfo) => async () => {
-  const [{ repository }, latestRelease] = await Promise.all([
+  const [{ repository }, { latestRelease }] = await Promise.all([
     pluginApiClient.getRepository({ ...project }),
-    getLatestRelease({ project, pluginApiClient }),
+    pluginApiClient.getLatestRelease({ ...project }),
   ]);
 
   if (latestRelease === null) {
@@ -42,7 +41,7 @@ export const getGitHubBatchInfo = ({
 
   const { branch } = await pluginApiClient.getBranch({
     ...project,
-    branchName: latestRelease.target_commitish,
+    branchName: latestRelease.targetCommitish,
   });
 
   return {
diff --git a/plugins/github-release-manager/src/sideEffects/getLatestRelease.test.ts b/plugins/github-release-manager/src/sideEffects/getLatestRelease.test.ts
deleted file mode 100644
index 15ef97d453..0000000000
--- a/plugins/github-release-manager/src/sideEffects/getLatestRelease.test.ts
+++ /dev/null
@@ -1,43 +0,0 @@
-/*
- * Copyright 2021 Spotify AB
- *
- * Licensed under the Apache License, Version 2.0 (the "License");
- * you may not use this file except in compliance with the License.
- * You may obtain a copy of the License at
- *
- *     http://www.apache.org/licenses/LICENSE-2.0
- *
- * Unless required by applicable law or agreed to in writing, software
- * distributed under the License is distributed on an "AS IS" BASIS,
- * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
- * See the License for the specific language governing permissions and
- * limitations under the License.
- */
-
-import { mockApiClient } from '../test-helpers/test-helpers';
-import { getLatestRelease } from './getLatestRelease';
-
-describe('getLatestRelease', () => {
-  beforeEach(jest.clearAllMocks);
-
-  it('should return the latest release with id=1', async () => {
-    const result = await getLatestRelease({ pluginApiClient: mockApiClient });
-
-    expect(result).toMatchInlineSnapshot(`
-      Object {
-        "body": "mock_latest_release",
-        "html_url": "mock_release_html_url",
-        "id": 1,
-        "prerelease": false,
-      }
-    `);
-  });
-
-  it('should return early with `null` if no releases found', async () => {
-    mockApiClient.getReleases.mockImplementationOnce(() => ({ releases: [] }));
-
-    const result = await getLatestRelease({ pluginApiClient: mockApiClient });
-
-    expect(result).toMatchInlineSnapshot(`null`);
-  });
-});
diff --git a/plugins/github-release-manager/src/sideEffects/getLatestRelease.ts b/plugins/github-release-manager/src/sideEffects/getLatestRelease.ts
deleted file mode 100644
index ef609cfd5e..0000000000
--- a/plugins/github-release-manager/src/sideEffects/getLatestRelease.ts
+++ /dev/null
@@ -1,41 +0,0 @@
-/*
- * Copyright 2021 Spotify AB
- *
- * Licensed under the Apache License, Version 2.0 (the "License");
- * you may not use this file except in compliance with the License.
- * You may obtain a copy of the License at
- *
- *     http://www.apache.org/licenses/LICENSE-2.0
- *
- * Unless required by applicable law or agreed to in writing, software
- * distributed under the License is distributed on an "AS IS" BASIS,
- * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
- * See the License for the specific language governing permissions and
- * limitations under the License.
- */
-
-import { PluginApiClient } from '../api/PluginApiClient';
-import { Project } from '../contexts/ProjectContext';
-
-interface GetLatestRelease {
-  pluginApiClient: PluginApiClient;
-  project: Project;
-}
-
-export async function getLatestRelease({
-  pluginApiClient,
-  project,
-}: GetLatestRelease) {
-  const { releases } = await pluginApiClient.getReleases({ ...project });
-
-  if (releases.length === 0) {
-    return null;
-  }
-
-  const { latestRelease } = await pluginApiClient.getRelease({
-    ...project,
-    releaseId: releases[0].id,
-  });
-
-  return latestRelease;
-}
diff --git a/plugins/github-release-manager/src/test-helpers/test-helpers.test.ts b/plugins/github-release-manager/src/test-helpers/test-helpers.test.ts
index eb359d06dd..c833efbca8 100644
--- a/plugins/github-release-manager/src/test-helpers/test-helpers.test.ts
+++ b/plugins/github-release-manager/src/test-helpers/test-helpers.test.ts
@@ -27,17 +27,15 @@ describe('testHelpers', () => {
             "getComparison": [MockFunction],
           },
           "getBranch": [MockFunction],
+          "getHost": [MockFunction],
           "getLatestCommit": [MockFunction],
-          "getOctokit": [Function],
-          "getProject": [MockFunction],
+          "getLatestRelease": [MockFunction],
+          "getOrganizations": [MockFunction],
           "getRecentCommits": [MockFunction],
-          "getRelease": [MockFunction],
-          "getReleases": [MockFunction],
           "getRepoPath": [MockFunction],
+          "getRepositories": [MockFunction],
           "getRepository": [MockFunction],
-          "githubAuthApi": Object {
-            "getAccessToken": [MockFunction],
-          },
+          "getUsername": [MockFunction],
           "patch": Object {
             "createCherryPickCommit": [MockFunction],
             "createReference": [MockFunction],
@@ -48,29 +46,14 @@ describe('testHelpers', () => {
             "replaceTempCommit": [MockFunction],
             "updateRelease": [MockFunction],
           },
-          "pluginApiClient": Object {
-            "baseUrl": "http://mock_base_url.hehe",
-            "getOctokit": [MockFunction],
-          },
-          "project": Object {
-            "github": Object {
-              "org": "mock_org",
-              "repo": "mock_repo",
-            },
-            "name": "mock_name",
-            "versioningStrategy": "semver",
-          },
           "promoteRc": Object {
             "promoteRelease": [MockFunction],
           },
         },
         "mockBumpedTag": "rc-2020.01.01_1337",
         "mockCalverProject": Object {
-          "github": Object {
-            "org": "mock_org",
-            "repo": "mock_repo",
-          },
-          "name": "mock_name",
+          "owner": "mock_owner",
+          "repo": "mock_repo",
           "versioningStrategy": "calver",
         },
         "mockDefaultBranch": "mock_defaultBranch",
@@ -80,12 +63,11 @@ describe('testHelpers', () => {
           "releaseName": "Version 1.2.3",
         },
         "mockRcRelease": Object {
-          "body": "mock_body",
-          "html_url": "mock_release_html_url",
+          "htmlUrl": "mock_release_html_url",
           "id": 1,
           "prerelease": true,
-          "tag_name": "rc-2020.01.01_1",
-          "target_commitish": "rc/1.2.3",
+          "tagName": "rc-2020.01.01_1",
+          "targetCommitish": "rc/1.2.3",
         },
         "mockRecentCommits": Array [
           Object {
@@ -128,12 +110,11 @@ describe('testHelpers', () => {
           "name": "rc/1.2.3",
         },
         "mockReleaseVersion": Object {
-          "body": "mock_body",
-          "html_url": "mock_release_html_url",
+          "htmlUrl": "mock_release_html_url",
           "id": 1,
           "prerelease": false,
-          "tag_name": "version-2020.01.01_1",
-          "target_commitish": "rc/1.2.3",
+          "tagName": "version-2020.01.01_1",
+          "targetCommitish": "rc/1.2.3",
         },
         "mockSelectedPatchCommit": Object {
           "author": Object {
@@ -148,11 +129,8 @@ describe('testHelpers', () => {
           "sha": "mock_latestCommit_sha",
         },
         "mockSemverProject": Object {
-          "github": Object {
-            "org": "mock_org",
-            "repo": "mock_repo",
-          },
-          "name": "mock_name",
+          "owner": "mock_owner",
+          "repo": "mock_repo",
           "versioningStrategy": "semver",
         },
         "mockTagParts": Object {
diff --git a/plugins/github-release-manager/src/test-helpers/test-helpers.ts b/plugins/github-release-manager/src/test-helpers/test-helpers.ts
index fc246ab4bc..a68926182c 100644
--- a/plugins/github-release-manager/src/test-helpers/test-helpers.ts
+++ b/plugins/github-release-manager/src/test-helpers/test-helpers.ts
@@ -17,10 +17,8 @@
 import { CalverTagParts } from '../helpers/tagParts/getCalverTagParts';
 import { getRcGitHubInfo } from '../cards/createRc/getRcGitHubInfo';
 import {
-  GhCompareCommitsResponse,
   GhCreateCommitResponse,
   GhCreateReferenceResponse,
-  GhCreateReleaseResponse,
   GhCreateTagObjectResponse,
   GhGetBranchResponse,
   GhGetCommitResponse,
@@ -28,24 +26,19 @@ import {
   GhMergeResponse,
   GhUpdateReferenceResponse,
   GhUpdateReleaseResponse,
-  Project,
 } from '../types/types';
+import { Project } from '../contexts/ProjectContext';
+import { ApiMethodRetval, IPluginApiClient } from '../api/PluginApiClient';
 
 export const mockSemverProject: Project = {
-  github: {
-    org: 'mock_org',
-    repo: 'mock_repo',
-  },
-  name: 'mock_name',
+  owner: 'mock_owner',
+  repo: 'mock_repo',
   versioningStrategy: 'semver',
 };
 
 export const mockCalverProject: Project = {
-  github: {
-    org: 'mock_org',
-    repo: 'mock_repo',
-  },
-  name: 'mock_name',
+  owner: 'mock_owner',
+  repo: 'mock_repo',
   versioningStrategy: 'calver',
 };
 
@@ -72,23 +65,28 @@ const createMockRelease = ({
   id = 1,
   prerelease = false,
   ...rest
-}: Partial<GhGetReleaseResponse> = {}) =>
+}: Partial<
+  NonNullable<
+    ApiMethodRetval<IPluginApiClient['getLatestRelease']>['latestRelease']
+  >
+> = {}) =>
   ({
     id: 1,
-    body: 'mock_body',
-    html_url: 'mock_release_html_url',
+    htmlUrl: 'mock_release_html_url',
     prerelease,
     ...rest,
-  } as GhGetReleaseResponse);
+  } as NonNullable<
+    ApiMethodRetval<IPluginApiClient['getLatestRelease']>['latestRelease']
+  >);
 export const mockRcRelease = createMockRelease({
   prerelease: true,
-  tag_name: 'rc-2020.01.01_1',
-  target_commitish: 'rc/1.2.3',
+  tagName: 'rc-2020.01.01_1',
+  targetCommitish: 'rc/1.2.3',
 });
 export const mockReleaseVersion = createMockRelease({
   prerelease: false,
-  tag_name: 'version-2020.01.01_1',
-  target_commitish: 'rc/1.2.3',
+  tagName: 'version-2020.01.01_1',
+  targetCommitish: 'rc/1.2.3',
 });
 
 /**
@@ -134,63 +132,39 @@ export const mockSelectedPatchCommit = createMockCommit({
 /**
  * MOCK API CLIENT
  */
-export const mockApiClient = {
-  pluginApiClient: {
-    getOctokit: jest.fn(),
-    baseUrl: 'http://mock_base_url.hehe',
-  },
-
+export const mockApiClient: IPluginApiClient = {
+  getHost: jest.fn(() => 'github.com'),
   getRepoPath: jest.fn(() => 'erikengervall/playground'),
-
+  getOrganizations: jest.fn(),
+  getRepositories: jest.fn(),
+  getUsername: jest.fn(),
   getRecentCommits: jest.fn().mockResolvedValue({
     recentCommits: mockRecentCommits,
   }),
-  getReleases: jest.fn().mockResolvedValue({
-    releases: [
-      createMockRelease({ id: 1, body: 'mock_releases[0]' }),
-      createMockRelease({ id: 2, body: 'mock_releases[1]' }),
-    ],
-  }),
-  getRelease: jest.fn().mockResolvedValue({
-    latestRelease: createMockRelease({ id: 1, body: 'mock_latest_release' }),
-  }),
-
-  getBranch: jest.fn().mockResolvedValue({
-    branch: mockReleaseBranch,
-  }),
+  getLatestRelease: jest.fn(), // TODO:
+  getRepository: jest.fn(),
   getLatestCommit: jest.fn().mockResolvedValue({
     latestCommit: createMockCommit({ node_id: 'mock_latest_commit' }),
   }),
-  getOctokit: () => ({
-    octokit: {
-      request: jest.fn(),
-    },
+  getBranch: jest.fn().mockResolvedValue({
+    branch: mockReleaseBranch,
   }),
-  getProject: jest.fn(),
 
-  getRepository: jest.fn(),
-  githubAuthApi: {
-    getAccessToken: jest.fn(),
-  },
   createRc: {
     createRef: jest.fn().mockResolvedValue({
-      createdRef: {
-        ref: 'mock_createRef_ref',
-      } as GhCreateReferenceResponse,
-    }),
+      ref: 'mock_createRef_ref',
+    } as NonNullable<ApiMethodRetval<IPluginApiClient['createRc']['createRef']>>),
     createRelease: jest.fn().mockResolvedValue({
       createReleaseResponse: {
         name: 'mock_createRelease_name',
-        html_url: 'mock_createRelease_html_url',
-        tag_name: 'mock_createRelease_tag_name',
-      } as GhCreateReleaseResponse,
-    }),
+        htmlUrl: 'mock_createRelease_html_url',
+        tagName: 'mock_createRelease_tag_name',
+      },
+    } as NonNullable<ApiMethodRetval<IPluginApiClient['createRc']['createRelease']>>),
     getComparison: jest.fn().mockResolvedValue({
-      comparison: {
-        html_url: 'mock_compareCommits_html_url',
-        ahead_by: 1,
-      } as GhCompareCommitsResponse,
-    }),
+      htmlUrl: 'mock_compareCommits_html_url',
+      aheadBy: 1,
+    } as NonNullable<ApiMethodRetval<IPluginApiClient['createRc']['getComparison']>>),
   },
   patch: {
     createCherryPickCommit: jest.fn().mockResolvedValue({
@@ -252,5 +226,5 @@ export const mockApiClient = {
       } as GhGetReleaseResponse,
     }),
   },
-  project: mockSemverProject,
-} as any;
+  // project: mockSemverProject,
+};
diff --git a/plugins/github-release-manager/src/types/types.ts b/plugins/github-release-manager/src/types/types.ts
index 04f53fd80a..8853efc71b 100644
--- a/plugins/github-release-manager/src/types/types.ts
+++ b/plugins/github-release-manager/src/types/types.ts
@@ -21,7 +21,7 @@ interface ComponentConfig<Args = void> {
 
 export interface ComponentConfigCreateRcSuccessCbArgs {
   gitHubReleaseUrl: string;
-  gitHubReleaseName: string;
+  gitHubReleaseName: string | null;
   comparisonUrl: string;
   previousTag?: string;
   createdTag: string;
@@ -30,7 +30,7 @@ export type ComponentConfigCreateRc = ComponentConfig<ComponentConfigCreateRcSuc
 
 export interface ComponentConfigPromoteRcSuccessCbArgs {
   gitHubReleaseUrl: string;
-  gitHubReleaseName: string;
+  gitHubReleaseName: string | null;
   previousTagUrl: string;
   previousTag: string;
   updatedTagUrl: string;