On my Lenovo laptop that has been happily running GhostBSD for 8 months or so, the latest upgrade results in the screen loading the mouse pointer and then just malformed graphics lines on the top of the screen. The option to just type in my password doesn't do anything and trying to get into other TTYs don't work via Ctrl Alt F1 - F4
After a hard power cycle, I can choose the boot environment of the backup before the upgrade and 12.1 Stable boots well. I've done this upgrade twice now with the same effect.
I'm not sure how to diagnose the issue - but wiling to learn

Further information available if you know what to ask for . . .
Cheers.