iOS 15 - Album Art Changed after copying to iPhone 13 Pro

Just got an iPhone 13 Pro. Setup went smoothly.
Everything loaded from my iPhone XS. No problems.

After my next round of lossless CD ripping, album cover scanning and copying to the new phone, the next time I launched Music on the iPhone the 6 albums I had just loaded had the wrong album art!

A couple of days later I added 2 more albums and the same thing happened.

Bizarre.

Has anyone else had this happen?
Is there a simple fix?
I have maybe 500 complete albums (many multi-disk) on the iPhone. It would be painful to reload everything.

Thanks!