After update last night watch is dead

plug it in, let it charge and afterwards do a hard reset (hold power button for 15 seconds). i always do that after an upgrade, just to be on the safe side

Won't fifteen seconds call your emergency contacts?  I usually hold it for fifteen seconds after the warning message disappears.

Fredrik_Coulter - the first message you get is indeed related to the emergency contacts, but if you keep the button pressed, a few seconds later the watch will reset ;-)

Don't worry about 15 seconds or whatever number others might suggest. Just keep the top left button pressed (through the Assistance message) until the watch shuts down. That's a hard reset.

I had a similar experience. My watch showed 1% battery after this update.

May not be the 4.10 update to blame.

I plugged my watch just to see if i'm in the 50% that got the update.

Garmin express automatically installed some language updates, and it stayed quite a bit on "syncing" 

After removing the watch i always shut it down (otherwise i always get wrong battery percentage).

It was 96%, after 3 hours -> 53%.

After another hard reset now i get 1.5%/h which is stilll quite a bit from the normal 0.4

I didn’t manually update my watch. My battery died after automatically updating last night.

In retrospect, I believe I went to bed with around 50% battery life.

The 10% warning woke me up in the middle of the night because do not disturb disabled itself after the update.

I powered the watch up this morning when I tried to check it and it showed 1%.

In the Connect app I see missing data until it powered up this morning, so that also supports the battery dying.

The battery drain must have been way higher than normal to drain 50% in less than a couple hours.

Yeah, I've started to do the same as part of my update routine. After update do a hard reset :)