Hi, we are looking to head down to Disneyland in June and my wife noticed Costco is going to sell a 3 day park hopper with lightning lane and $30 in park credit for $449 starting in May. We were planning do a 5 day park hopper but this seems like a good saving compared to a regular 3 day park hopper. Do you know if Disney allows you to upgrade a ticket like this from 3 to 5 days and if so how do they calculate the cost basis for the upgrade? Thanks