I bumped on the same situation.
I actually don’t remember what keys I pressed (like Ctrl + Alt + F2, Ctrl + F1 and so on) but after some of them I got a usual login promt. I entered ‘root’ as login and it authorized me without any password.
Then I run ls /dev/disk/by-label/ and saw ‘hassos-data-old’ disk here. But HA requires ‘hassos-data’ disk, so I renamed ‘hassos-data-old’ to ‘hassos-data’ with the following command:
e2label /dev/disk/by-label/hassos-data-old hassos-data
After reboot I got system running as before moving data disk!