You will check in online when your booking window opens. You have to be paid in full to do this, though the PIF date is at 75 days, so you may need to be paid earlier to get access when your window opens. After you check in online at 3 a.m. ET, you will be able to select a port arrival time from the choices available at that time. This time will generate your boarding number, but you won't get that until after you actually check in at the terminal. No matter when you pay your balance, you won't be able to check in online until your window opens. [120 days platinum, 105 days gold, 90 days silver, 75 days first time cruisers]