Solved (in my case): subscription group version stuck in READY_FOR_REVIEW, blocking first submission (2.1(b)) I was stuck for over a week with the same problem many of you describe: first app submission with auto-renewable subscriptions, everything configured and "Ready to Submit," but the app kept getting rejected under 2.1(b) because the subscriptions couldn't be attached to the build. The "In-App Purchases and Subscriptions" section wouldn't let me submit, and the App Store Connect API returned: STATE_ERROR.SUBSCRIPTION_GROUP_VERSION_INVALID_STATE — "Only versions in 'Prepare for Submission' or 'Developer Rejected' state can be submitted." The subscription group version was stuck in READY_FOR_REVIEW — an orphaned state left over from a previous rejection, with no active submission referencing it. What actually worked for me: The group version eventually moved back to PREPARE_FOR_SUBMISSION on its own (server-side). In my case this seems to have happened when a previous submission finished processing — NOT immediately when I cancelled a submission. I cancelled submissions several times over the week and it did NOT unlock right away. Once the group version was in PREPARE_FOR_SUBMISSION, I created a new submission and — this is the key part — added THREE things explicitly: the app version (with the build), the subscription GROUP, AND each subscription. Adding only the group is not enough; App Store Connect warns "new subscription groups must be submitted with an auto-renewable subscription." Once all items were in the package, the "Submit for Review" button activated. What I could NOT confirm (being honest): What exactly kept it stuck for a full week, or what precisely released it. The API doesn't expose completion timestamps for submissions or the history of which item held the group. My best guess is that a prior submission finishing server-side released it, but I can't prove it. Cancelling a submission may be the right action, but it is NOT instant — the release can take hours/days to propagate, not minutes. My mistake was concluding too early that cancelling "didn't work." Things that did NOT help in my case: deleting/editing the group localization (returned "unmodifiable"), editing the subscription reviewNote, and Apple Developer Support (no response by email). I did NOT delete the products — that's irreversible (you lose the product IDs permanently) and, since the problem is the group version state and not the products, it likely wouldn't have helped anyway. Bottom line: check the group version state via the API. If it's PREPARE_FOR_SUBMISSION, build a submission with app + group + subscriptions all attached. If it's stuck in READY_FOR_REVIEW, cancel the blocking submission and WAIT — re-check the state periodically instead of assuming it failed. Hope this saves someone the week I lost.