Bell Services will pick up your luggage on debarkation morning, possibly around 7am (though you will get a letter telling you the correct time). It is then taken to the port by truck and you'll see it again in your stateroom onboard.
DCL Transfers generally pick-up early- to mid-morning, possibly as early as 8am. It varies each cruise based on the number of guests with transfers from each resort. Again, the letter you receive the day prior will give you the exact time to be ready for pick-up. It's possible to have a bus that is just guests of your resort, or you may be one of two or three resorts on that bus that morning.