May be unrelated to the firmware update (my hub updated apparently without incident around 5pm EST yesterday, everything still working normally) but throwing this out there as a data point:
Sometime in the wee hours this morning my hub went offline (as evidenced by nothing working in response to scheduled events or Alexa interaction). Discovered hub with no light on, though it was powered and still warm. Odd, would have expected some non-green colored light on if it had power and was not completely dead. Panicked, I unplugged, replugged, and thankfully saw the red light > blue light > green light sequence as it came back on line. Things seem to be working now, though I did find Device Health had somehow turned itself back on. Aside from ‘no DC power’ (not the case here) is there any fault scenario which intentionally turns off the status indicator light?