The timer function really isn't the most useful - it's pretty much been broken since day one. You're better off just to use a timing app or built in utility in your phone. (the APC, once the timer expires beeps incessantly until you stop the cook, despite the fact that it continues to hold your cook at temperature until you stop it). Only way to clear the beeping is to toggle the cook off then on. (hence why using any other timer is better).
Maybe they'll finally fix this once they give us a scheduler function (but, that's also been on the wish list for a few years now).