If there are multiple passengers in my reservation, can I chose to upgrade only some of them with miles using EasyCheck-in Online?
All travelers attempting to upgrade who are listed on the same reservation must use the same form of payment when purchasing upgrades. For example, if a family of four is traveling on the same reservation, the logged-in Mileage Plus member requesting the upgrades must upgrade all the passengers in the reservation. Payment for the upgrades will be deducted from the logged-in customer’s Mileage Plus account.