I had a fun 3 hours the other day. I was using my iPhone (SE; last iOS 9 that was available) as I normally do, but all of a sudden the iPhone restarted and my screen showed the Apple logo. It sat there for a few minutes doing nothing. I restarted the iPhone. It went back to the black screen with Apple logo. I tried a hard reset. Same thing. Finally, I set the iPhone in recovery mode, plugged it into iTunes on my Macbook and Apple said it needed to update to the latest iOS. Not having any other options, I did that. It went through downloading 2GB of the iOS 10 update, rebooted and then hung again on the black screen with Apple logo. The download finished and appeared to have been retained on my macbook. I put the iPhone into recovery mode again, updated, and then picked my latest backup from August 15th. I followed the onscreen steps and was finally able to get back into my iPhone again.
Two other people I know had this happen to them.
Anyone else go through this forceful update?