Control App Store release timing: configure phased release, pause/resume/complete a rollout, or manually release a version held in Pending Developer Release

Documented steps

1. Choose the release mode via the appStoreVersion releaseType attribute: AFTER_APPROVAL (release as soon as Apple approves), MANUAL (hold for an explicit release request), or SCHEDULED (release automatically at earliestReleaseDate).
2. For SCHEDULED, set attributes.earliestReleaseDate (ISO-8601 date-time) on the version, via PATCH /v1/appStoreVersions/{id} if changing it after creation.
3. To roll out gradually, create a phased release: POST https://api.appstoreconnect.apple.com/v1/appStoreVersionPhasedReleases with body {"data":{"type":"appStoreVersionPhasedReleases","attributes":{"phasedReleaseState":"ACTIVE"},"relationships":{"appStoreVersion":{"data":{"type":"appStoreVersions","id":"<versionId>"}}}}}
4. phasedReleaseState values: INACTIVE (not started), ACTIVE (rolling out over about 7 days to an increasing share of users with automatic updates on), PAUSED (you paused it), COMPLETE (available to all eligible devices).
5. Pause an active rollout: PATCH https://api.appstoreconnect.apple.com/v1/appStoreVersionPhasedReleases/{id} with {"data":{"type":"appStoreVersionPhasedReleases","id":"<id>","attributes":{"phasedReleaseState":"PAUSED"}}}
6. Resume by PATCHing the same resource back to ACTIVE.
7. Push to 100% immediately by PATCHing phasedReleaseState to COMPLETE.
8. Remove phased release entirely (revert to a standard all-at-once release) with DELETE https://api.appstoreconnect.apple.com/v1/appStoreVersionPhasedReleases/{id}
9. For a MANUAL version sitting in appVersionState PENDING_DEVELOPER_RELEASE, publish it: POST https://api.appstoreconnect.apple.com/v1/appStoreVersionReleaseRequests with body {"data":{"type":"appStoreVersionReleaseRequests","relationships":{"appStoreVersion":{"data":{"type":"appStoreVersions","id":"<versionId>"}}}}}
10. After a successful release request, re-fetch GET /v1/appStoreVersions/{id} and watch appVersionState move through PROCESSING_FOR_DISTRIBUTION toward READY_FOR_DISTRIBUTION.
11. Official docs: https://developer.apple.com/documentation/appstoreconnectapi/post-v1-appstoreversionphasedreleases | https://developer.apple.com/documentation/appstoreconnectapi/phasedreleasestate | https://developer.apple.com/documentation/appstoreconnectapi/post-v1-appstoreversionreleaserequests