The only slight bug I have noticed is the ‘Boost Updating’ thing so see my post. Sonos are investigating it but it does not seem to affect playback at all

I had to run it twice as my sub on the arc system failed 

Only issue I had

Thx SarahN. I managed to get hold of someone at the technical support and she promised there’ll be no problems with this update. Unfortunately I haven’t found the number of this update. 

YES!

I can no longer control my SUB or either of my Sonos1’s in the room with the Playbase.

They don’t appear anywhere on the app any more!

Basically making the whole system uncontrollable

Unhappy I am !

This is not an issue with the firmware update, but with the update process itself.  If you restart your router and the sub and sonos ones, you should see everything in the Sonos app again.  

Same issue here. Restarting my Wi-Fi and unplugging the speakers does not work. My One is currently even listed as "updating" even though it's unplugged.

What did Sonos support say when you contacted them?

Big bug for me : lost all my system since update,  lost voice assistant too.