I don't think you'll know your specific dining rotation until you get onboard. However, with a 7-night, you have two of the restaurants twice and one of restaurants 3 times. For the one with 3 visits, one of those will be Pirate night. An easy way to tell which night is Pirate night is to look at the list of bookable onboard activities and see when they offer Pirate makeover. That would be on Pirate night. Hope you have a great cruise.