If we haven't confirmed your upgrade by the time you check in for your flight, you will be added to the Upgrades list at check-in, so there's nothing that you need to do after submitting your original request. Our upgrade systems process requests until three hours before flight departure, at which point our gate agents will handle all remaining upgrade requests.
*On flights equipped with United Premium Plus, we will process requests to upgrade to business class for customers ticketed in United Premium Plus (fare classes O, A, R) before processing requests for customers ticketed in economy.
Upgrade priority on United Premium Plus
On aircraft with United Premium Plus, we’ll first process United Polaris business class or United Business waitlists for all members who have purchased United Premium Plus seats, using the same priority order that applies to all upgrades. We’ll then process waitlists for members with United Economy seats.
New waitlist requests for MileagePlus Upgrade Awards, Regional Premier Upgrades and Global Premier Upgrades can be made until 24 hours before departure.