I had the same problem where my machine would restart mid-afternoon and I'd lose unsaved work, which was infuriating. The thing most people miss is that even if you set Active Hours, Windows will still eventually force a restart if you haven't restarted in like two weeks - so you can't just ignore it forever. Your best move is to manually check for updates on your own schedule (Settings > Update & Security > Check for updates), install them, then restart when you're ready, rather than letting it run on autopilot. You can also try disabling the "Windows Update" service entirely if you want total control, but then you're responsible for remembering to update, which most people don't do and that's its own security headache.