In the middle of the night my watch, which was on the charger stand on my nightstand, started binging. Not like an alarm, but just one "bing" and the face lit up. Loud enough and bright enough to wake me up. After the third bing in 10 minutes, I looked at it and there was an announcement on the watch that watchOS 6.0.1 was available for update. It helpfully offered that it could perform the update overnight, so I tapped on the button to allow that and went back to sleep. In the morning, when my iPhone alarm clock went off, it was followed by binging from both it and the watch. The watch was on a screen saying I needed to agree to the installation terms, as was the iPhone.
So this morning I went ahead and installed 6.0.1. Mickey and Minnie talk, but Siri is now silent. I guess I have to go find the settings to get that back now.
C'mon, Apple, no need to wake me in the middle of the night for a watch update unless it's going to kill me in the morning if I don't update it immediately!