HF21 is in a testing phase and we will absolutely address any necessary bugs (if any) that are identified by us, witnesses, or other developers during this testing phase. We will also need to give exchanges an appropriate amount of time to upgrade before the hardfork date. In the meantime, it’s full Steem ahead on development for SMTs. We aren’t waiting around to get started on this - in fact, SMTs have been back in active development for over a week now.