This is really weird.
In my 45 years in the Industry, Engineer NOT Pilot, and at several different Airlines, we have always chocked aircraft on arrival (yes after stopping) then release the brakes.
IF it is just a turnround then that is it normally, however IF it is on an extended turnround and definitely if overnight, once the brakes are cooled off brakes are parked and chocks left in.
That includes ALL the aircraft I have ever been involved with, including B727s.