When we did it in 2007, we were allowed to stay onboard as everyone exited -- all our paperwork was done for us the night before. It seems they don't allow that anymore (we were doing the 10-day with the 14-day WBTA), unless it was because it was a foreign port and we were returning to and leaving from the same port
But we absolutely loved being onboard when the ship was empty; going to the disembarkation breakfast without luggage and no sadness about having to leave or rushing. Loved having the adult pool to ourselves for three hours; loved going back to our room for a nap before boarding began! And we were lucky because they were two different cruise types, the menus changed for the WBTA and we had lots of new selections. We also ordered more room service and pizza on the trip home as we did burn out on too much rich food LOL.
I'd love to do another.
Have a great time.