Let Disney move your luggage....call luggage services/bell services first thing in the morning when you want to leave. Then, once that's taken care of, I like to head off to a park for a few hours before lunch. Then, I leave the park and go to the 'new' resort, and checkin. Most times I have been able to get into my room then, unless it's a DVC situation. I eat some lunch and then head back out to the parks.
It usually takes until late afternoon for your bags to get to you at the new resort.