Same here, experiencing this issue since the middle of last month. Did you use App Store Connect API to upload binaries? We did, and wondering if it has something to do with the issue... because our release on the beginning of last month, which was NOT uploaded with App Store Connect API, was released successfully at specified date.

Has anyone experienced this problem with Xcode 12.x? We feel the occurence of this issue had increased since we upgraded Xcode from 11.3.1 to 11.5. Upgrading to 11.6 didn't have effect. After rolling back to 11.3.1, it seems to have gradually decreased. We wonder if upgrading Xcode to 12.x affects this problem or not.