Gail Badner, I have been trying to reproduce this and haven't been successful.

I added a commit in my fork for a test case https://github.com/Naros/hibernate-orm/commits/HHH-4803.

When I test this, EntityZ is never proxied so the #getTargetFromProxy isn't called when creating the CollectionChangeWorkUnit. Perhaps you could skim my test case and let me know what I might have overlooked based on your provided example in this JIRA.