Update: I have now received a response from Apple Developer Support regarding Case 102966589079. Developer Support confirmed that the rejection is expected because the minimum required iOS version is now iOS 13, and that individual exceptions cannot be granted. I also verified the exact date of our last successful iOS 11 upload in Xcode Organizer: September 9, 2026 at 12:49. The build was accepted with warnings only and was released on the App Store on September 10. The same MinimumOSVersion = 11.0 was rejected with error 90068 on September 17. So the remaining question is: on what exact date did Apple begin enforcing the iOS 13 minimum, and was that specific enforcement date publicly announced beforehand? Feedback Assistant report: FB24879771

Update: I have also filed a Feedback Assistant report for this App Store Connect validation issue: FB24879771. It includes the upload history, screenshots of the previous successful iOS 11 upload and the current Error 90068, as well as additional reproduction details.