You can make it not reboot with group policies, not commonly known though - most people try the registry stuff which doesn't seem to work consistently. Been running Win10 Pro for a couple years, never had a single unwanted reboot, once went nearly a year without doing a single update.

Specifically, in group policy:

Computer Configuration > Administrative Templates > Windows Components > Windows Update > "Configure Automatic Updates" and "No auto-restart with logged-on users for scheduled automatic update installations"