Yessir. It’ll flash, but hangs on blue led after reboot. Never goes green. Using tftp as instructed.
EDIT: tried your method for 21.02.0 just in case, no go. And I was able to successfully revert to 19.07.9 so that's a little progress...
EDIT 2: also tracking the issue in HooToo Tripmate Titan HT-TM05 Travel Router Upgrade with @xabolcs and @arrmo