Kingdommagic.com has a promotion pay for a 3 day pass recieve a 4 day pass. I was going to buy a 5 day pass when I saw this proomotion. I don't think there would be any benefit in buying the 3 day pass(getting the 4 day pass) and trying to upgrade(add a day) at the parks. I think I would be charged more at the parks for upgrading because I wouldn't get the pay in advance price. Is this correct?