Hello fellow travelers: I created an account to thank all of the previous posters for your expert advice and information. I also wanted to share my experience with a recent booking.

Back in August 2022, I booked two tickets (for my wife and one kid) from ORD to TPE for May 2023 and returning a month later. I used my United miles and booked the two business class tickets using United’s award site. The cost for each ticket was 168,000 miles + $38.58. I would have booked four tickets but only two seats were available for booking with miles.

On 1/1/2023, I booked two B class tickets (highest economy fare option) on evaair.com for myself and my other kid; for the same May and June flights that my wife and other kid are already on. I called Eva Taipei’s reservation line to see if there were Z class seats available, but they were closed, so I just decided to take a chance and booked two B class tickets and hoped where were upgrade seats available. I figured I had a good chance since the flights had either two or three business class seats booked.

Immediately after booking the two seats on evaair.com, I tried to request upgrades to business class on United’s Star Alliance Upgrade site, but I got the “The traveler has the same name as an existing traveler on this flight” error that other people have gotten in the past. After spending over an hour trying different things, I finally got it to work. What worked for me was: entering in all of the required info plus my ticket number. The key was that I made sure there was no space in the ticket number (Eva’s confirmation email had the ticket number with a space after the first three numbers). Also key was that my son has a hyphenated last name, but since United’s site doesn’t allow hyphens, I entered a space between his two last names. I think that it may have also helped that almost two hours had passed from when I booked the tickets on evaair.com; which may have allowed enough time for both the Eva and United systems to see my ticket. It was 30,000 miles for each flight per person, so I used 120,000 miles for the roundtrip upgrade for my son and me. The miles were immediately deducted from my United account, and I was able to select my business class seats on evaaircom.