Sure, can change it to 1.0.20-hotfix-1 or can edit debian/watch to skip the -hotfix tag and change it to 1.0.20-1. Or use 1.0.20-1 and let uscan whine about 1.0.20-hotfix.
Given the changes all around, I don't think we want to actually push into Debian until 1.1.0 is released anyway. So whether the changes are representable or enormous or whatever doesn't really matter. What do you think: -hotfix or not -hotfix? Cheers, --Barak.