If you decide to have Bell Services come and pick up your luggage (highly recommended), seriously consider stopping by the Bell Services desk the afternoon/evening before the switch and set up a time for them to do that. If you wait until the morning you check out and then call them, you may may be waiting a very long time before they get around to you. If you set an appointment, they will be there on time. We've done it many times and they have always shown up at our door 5 min before the scheduled time. And don't forget to tip the CM on lock up and delivery.
Luggage transfers happen in a coordinated manner across all the resorts. The process begins about 1pm and typically takes 2-3 hours to complete. Regardless of when you get your bags to Bell Services, don't expect to get them at the new resort until at least 3, more likely 4pm - and occasionally later.
As mentioned, you have to be in your room and call Bell Services in order for them to deliver your bags. Or, you can stop by Bell Services yourself and pick them up (assuming they've arrived yet).
If anything that's being transferred needs to be refrigerated or frozen, Bell Services can handle that too. But you do need to tell them what needs to be kept cold, and have it separated in its own bag.
It's really a very easy process.
Steve