While that modal does exist, Windows for some reason does not give it always-on-top status, so if you have anything fullscreen running you'll never see it. Ther

While that modal does exist, Windows for some reason does not give it always-on-top status, so if you have anything fullscreen running you'll never see it. There also seems to be a limit to the number of times you're allowed to delay a reboot, though I'm not entirely sure on that.