A few days ago, a bug was introduced to PrPro where keyframes are getting lost after saving a project and then re-opening it. Almost all of the recent bug reports I see on this Beta forum are about that bug.
The bug has already been fixed internally. We just need to test the fix thoroughly and then make it available via the CC Desktop App. Look for it at Pr 23.6 Beta build 031 or higher. Sorry for the problems this has cuased for those of you who help us out withthe Beta builds.