Most people let rigor pass before they freeze the meat. I think it is easier to tell when rigor has passed by moving joints or seeing how flexible the meat is. If you are doing a bunch it's probably easier as part of your butchering system to do it then. For most people I think it is more convenient. I freeze mine first though. I've worked out a system where I take the meat out of the freezer on Sunday and thaw it in the fridge, then cook it on Thursday that works for me. It means I do have to plan ahead when I want to eat chicken, I can't just take it out and thaw it.
If you cook the meat before rigor sets up you don't have to age it but that pretty much means you are only butchering one at a time and it goes straight from butchering to cooking. If rigor sets up it will be tough.