Airlock activity is so little that it might as well be expanding air (the bucket sits in my garage without extra heating or cooling, subject to the temperature cycles visible in the graph). There is nothing really in the bucket the hydrometer could be stuck against on my opinion, but I‘d have to open it to check - which I’m reluctant to do because of infection risk, obviously.

Taste testing I didn’t think of until now, good thinking. Will do tomorrow. If it’s completely dry, the calculations must be way off.