People blame IT too much. RC books hundreds of cruises per day. There's not some piece of code that said "oh I'm going to give this reservation a random payment and deposit date"
Still seems like something we don't know (not that it's the fault of the OP)
RC isn't about to make rules more strict than they need to. It took a few days once Canada changed their rules for RC to update its own. PRobably the same thing here.
Was this some sort of special reservation? Deposit due date the same day as the final payment date, both in the future, neither would fit the 90 day payment window.
Only one ship is sailing out of Tampa right now, a Carnival ship.
She's due back in Thursday, though I'd be shocked if those folks don't get a bonus day at sea.