They seem to be getting less aggressive, but I've had my machine reboot with less than half an hour of notice. No notice before leaving the machine, return 30 minute later to find it rebooted. So "just mark every 2nd Tuesday of a month as patch day and never leave your machine(s) unattended on that day and you won't have surprises!".
I've also had (in a recent month) them reboot overnight, aborting long running processes that I had to clean up and restart, after explicitly checking for updates before starting those processes (none being found), and making sure my "active hours" were set such that it shouldn't restart.
Earlier this year I had a patch mid-cycle (not close to the normal patch Tuesday) that caused a reboot too. IIRC it was a flash-for-edge/ie update. An update for a feature I don't use/want and can't remove caused a "random" reboot at an unpredictable time. Ta muchly...
I understand MS wanting to get away from their desktop OS's insecure reputation which is in part caused by people never installing updates meaning that worms and other malware were able to run rampant relatively unchecked, but they seem rather wrong headed about how pushy to be in fixing that.