There was a video on LTT about this. From what I remember the conclusion was that if you shut down the laptop while connected to power, it remembers the fact and wakes up in the middle of the night to apply updates and shut down again, assuming the power cable will remain connected so there wouldn't be an impact on the battery. But of course, most people (I think) disconnect the power cable once the laptop is shut down. Windows still wakes up, sees the power cable disconnected, and goes 'oh well' and proceeds to update anyway.