I upgraded to 12.0 and also manually to 12.1. Unfortunately, I get into a bootloop, so this does not work for me. Once manually downgrading to 11.5, things work again.

 

I cannot get a diagnostic after upgrade as I only get the bootoop, I also tried a fresh 12.0 install, which also failed. I am attaching the diagnostic log from 11.5 after manual downgrade.

 

Thanks for your help!!!

tower-diagnostics-20230627-0042.zip

If a new stock flash drive does the same it suggests some compatibility issue between your hardware and the newer kernel, look for a BIOS update, failing that re-try when a new Unraid release with a newer kernel is available.