For the most part, help the FA clean up then head to the hotel. You acknowledge the next day's flights on the app and they release you within a few minutes of that. Sometimes they forget, and a quick phone call to scheduling remedies it. Sometimes they release you early while you're still taking care of things, and there again a quick phone call will usually fix the misunderstanding. If they need you to standby because something's going on, or they need to extend you, they'll usually call you as soon as you open the door, or have one of the ground crew tell you to call scheduling.