When I purchased my SB back in October of 2015, it was plagued with sleep/hibernate issues. Failing to wake from sleep, getting hot during sleep, battery draining during sleep, Windows Hello not working after sleep, etc., etc. It was very, very frustrating trying to work with a computer when it was always a roll of the dice whether it would actually turn on or not. After many hours spent reconfiguring settings and many updates, my sleep/hibernate issues appeared to be fixed. Now, since the Anniversary Update, my sleep/hibernate issues have returned. When the computer is on battery, and it goes into sleep, it will often not wake up the next day, even if it has been plugged in over night. I have to press and hold down the power button for 30 seconds and then do a cold boot from there. I have all my settings configured to sleep, and never to hibernate. I have done the two-button salute (power and volume-up). I have experimented with various combinations of sleep and hibernate. As has become the norm with the Surface Book - every update is one step forward and two steps back.