Update: this is resolved for me, at least to the point of both items now being properly submitted. https://developer.apple.com/forums/thread/841767?answerId=901299022#901299022 https://developer.apple.com/forums/thread/840984 Following the App Store Connect Engineer's steps posted above (cancel the existing stuck submission first, wait for status to flip to Developer Rejected), I got past the "add an app version" error. What actually worked for me: instead of clicking "Add for Review" directly, I clicked the caret/dropdown arrow next to it and chose "Draft iOS Submission" from that menu. That opened the draft correctly, with the app version already selected and the In-App Purchase listed alongside it, and the "Submit for Review" button active. Both my app version and the IAP now show status "Waiting for Review." Posting this in case it helps anyone else who lands on this thread with the same symptom (Draft Submission stuck saying "add an app version for the selected platform," with no version selector available anywhere in the panel). The fix for me was cancelling the existing submission first, then using the caret dropdown next to Add for Review to select "Draft iOS Submission" specifically, rather than clicking Add for Review directly or creating a fresh draft. Will update again once the actual review comes back. Thanks to everyone who chimed in.

Thanks for the reply. To clarify, I did search before posting, several threads describing this exact "In-App Purchases and Subscriptions section missing after rejection" issue, going back a while. That's actually part of why I posted, since in the threads I found, the resolution in each case was Apple support manually pushing the IAP status forward on their end, not something fixable from the developer side through the UI. If there's a UI-based fix you know of that worked for you, I'd genuinely appreciate a pointer, that would save me the wait on my support ticket.