I belive the average time is between 9 and 10 o'clock, my cruise was EXTREMLY lucky because DCL rewarded their staff and let them get off and the cruise stayed at key west until 12:30 am!!!! (and you MUST watch the sunsets, they are beutifull)
Since it's not a definite time every cruise, be sure to read your Navigator. It will definitely state the ALL ABOARD time for your cruise. If you're still unsure, ask the CMs when you leave the ship.
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