Ubuntu MATE 16.04.2 kernel panic on RPI3?

Hi community :wave:

When I updated my RPI3 via SSH, after I rebooted I found myself on 16.04.2.:neutral_face:
Then, I shutdown for the end of the day and the next time I started it up… KERNEL PANIC!:rage:
I was forced to use an old backup with a password I FORGOT!
How do you avoid this problem?