The ships time will be set to whatever the local time is. So on the east coast, it will be EST, and when you sail through a time change, the ships clock will also change. Sorry I cant help with the ports youre going to but I believe all but Cozumel are on EST while Cozumel is CST???? Hopefully someone will reply, but you can also do a search too. Your daily newsletter on board will also remind you the night before to adjust your clocks.
Actually, I was looking thru some old Capers from our last cruise and in big letters it says on each port day PLEASE STAY ON SHIP TIME.
I think you should check with the cruiseline, but on Carnival, we've always stayed on ship time - which is the time zone in which you begin you cruise.
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