Booked my iphone Battery servicing though apple we...

Booked my iphone Battery servicing though apple website. When went to drop off my phone they said they don't follow apple's schedule. I had to put my name and number there. They called me back after a month. Battery replacement shouldn't take more than 15 to 30 minutes however they explained due to their process (which is very poor) they have to be fair to all their other customers and keep everyone waiting for over 8 hours for their repair. I have to be without my phone from 8:30 am till 5:00pm. Not satisfied.