If it’s really supposed to have better battery life with Ubuntu Touch, the only thing that might solve the problem is reflashing it, and formatting userdata. Maybe going back to the old version as well.
You could backup the userdata, using tar via SSH. It won’t take as long as backing up the entire drive, unless you are using a ton of space. Well, actually, not sure how slow tar is on it. Maybe don’t compress it. Or use rsync or something.
Waydroid doesn’t seem to work on it, using the latest version either. No idea if it works using the old version. Somebody with a different device, had issues using Waydroid too, no replies though.
Since I might do absolutely nothing to use it as a phone, I might not reflash it or anything.
Maybe I need to flash the latest Rabbit OS as well. That could possibly break Ubuntu Touch though.