I can confirm @nukem1232 observations: I also let my flashing being stuck at 31%, I waited for at least 5 hours. After that I forced restart of my (Chrome)box and it booted nicely to HAOS and HAOS instance is reachable locally. So, it seems like flashing indeed continued despite frozen system(*). But I can’t comment about DNS issues, HA cloud access, etc. (haven’t tried it yet).
(*) One clarification: When I said before that flashing with Balena got stuck at 31%, in fact it means that the whole OS is frozen, not just Balena etcher.