In case anybody else runs into this, I figured out what I was doing wrong. Xcode 15 added a new step at the beginning for distributing an archive. I was choosing "TestFlight & App Store" in that first step (which seemed to make sense). I just tried choosing 'Custom' instead, and that takes it to the normal workflow for uploading an archive, and it works from there.
davelevi
Users receive reputation points by contributing quality content to the forums.
Posts include post and replies published on the forums.
Post authors can mark replies as Accepted to indicate successful solutions.
Apple Developer Forums admins can mark replies as Apple Recommended to indicate an approved solution
Last seen
User for