We just did this for our recent stay. We stayed at POR and then moved to SSR. We left our luggage at bell services at POR in the morning and then went to the parks on Sunday. They said our luggage would be delivered to SSR between 1-3 pm that afternoon. We left the parks around 3pm, went to SSR and checked in and then went to Bell services there to get them to take our luggage to the room.
It worked pretty well, but they wouldn't deliver the luggage directly to the room in the new resort, we had to be there for bell services to do this. Let me know if you have any questions!