Regular brake maintenance isn't a bad idea guys. I go over mine twice a year, mostly because I live in Canada and our roads are very salty in the winter.
What I generally do is a good cleaning (debris can cause pads to stick), inspection so I don't get caught with my pants down, clean and lube slide pins, and then push pistons down to ensure freedom of movement.
This means that I don't get stuck calipers. Grinding metal from stuck pads doesn't happen. Pads unexpectedly wear down? I don't care, I get to pick my time to fix it.
So to answer the OP question, the rear brake require the pistons to be tired a few times. Line them up as per the maintenance manual in the diy section on this site. You only have to turn them a couple of rotations and the pistons can then be pressed down safely.
Sometimes the piston boots twist a bit, take your time and back off as necessary.