Originally Posted by UA Insider

Hi Everyone,

I wanted to let you know that tickets upgraded with a Global Premier Upgrade, Regional Premier Upgrade or a Mileage Upgrade Award may initially display the message, “A modification has been made to your itinerary. Please contact United Reservations to have your ticket reissued.” We’ll be running a process to synchronize these reservations automatically over the course of the next day, but, this process has not yet begun. Your flights will remain upgraded, but, in the new system, we need to take an additional step to match your reservation with your ticket (e.g. put it back in synch).