I had to figure out how to request a United upgrade after booking when I booked an economy ticket for a long-haul flight and later realized I wanted a bit more comfort. After purchasing, I logged into my reservation and saw upgrade options using miles, but I still had questions about waitlists and eligibility. My plans ended up changing anyway, so I needed to modify the booking. Calling 8 7 7-2 9 7-0 6 9 9 made everything easier—they explained how upgrades work and helped me adjust my flight at the same time. It saved me a lot of back-and-forth.
