We were in Disney a month ago and had two reservations - one with our points and one with rented points (my parents traveled with us so we got a two bedroom instead of the one bedroom we usually get). When we checked in I just told the CM and she said it was fine, but we would have to check out and check in again (our room category was the same as well), but we didn't have to switch rooms. On the designated day, I just went to the front desk and told them the situation and we got new room keys. Only took a few minutes. Plus, they did an extra Trash and Towel service for free!