If there's something written into your service agreement, they are the party you should contact about the nitty gritty. Otherwise, we can only guess.
I had to cut down my Direct TV bill so I went from 3 to 2 receivers. I got the box to send it back with, but I don't remember which receiver to send back. I have an old HR24. Can I just send that back, and keep my 3 receiver on without getting billed for it?.