You're right, they don't have to waiver all rights. What can happen is, if they decide they want to advance again, (1) they can be a scout instead of starting all over and be a recruit cuz to be a recruit means to be a new member...
-or-
if they were a high level rank (i.e. enforcer, guardian, council member) they can go back to being where they left off and not be put as a scout.