The deck party starts at 9:45. The characters appear around 10:10/15. It goes until 10:30 easily. The buffet is open during the deck party on the side of deck 9. I remember that the first cruise was tropical night & the kids were all wound up. We went to get something to eat after the party was over & DS just crashed. He disolved right there in line since he was finally letting himself be tired. That was 11. DH took the kids to the room & I filled a big plate for us.
You will see many kids in their PJs the next morning. We don't book excursions so we can go back to our room for a bit until we are ready to catch breakfast & get on a tender to explore.