I turned up without an appt because #yolo. 10 mins in the queue and 10 mins at the Genius Bar with the nerd. They have no check for shutdown, just the range of serials potentially affected, so as long as you say you're suffering and your phone serial is in the range they'll book you in. If you can live with the problem I'd maybe give it until after Xmas when the battery stock levels should have stabilised and they'll do it while you wait instead of having to make two trips.
I turned up without an appt because #yolo. 10 mins in the queue and 10 mins at the Genius Bar with the nerd. They have no check for shutdown, just the range of serials potentially affected, so as long as you say you're suffering and your phone serial is in the range they'll book you in. If you can live with the problem I'd maybe give it until after Xmas when the battery stock levels should have stabilised and they'll do it while you wait instead of having to make two trips.