Same here. I was able to add a version to prepare for submission, but after an hour when I got back to the page refreshed, It was gone. Like what you described, not able to add anymore regardless of any version number I used, and gave the same error messages.
gobassky
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