So, to sum up...
Originally Posted by
evergrn
My credit report has summer 2019 (not spring 2018) as the account open date for my wife's AMEx card for which I'm the authorized user.
Your wife added you as an authorized user to her Amex card in summer 2019.
Originally Posted by
evergrn
...the rep brought up that my Travelbank UA card was a new account and indicated that was the hold-up. That's in spite of the credit report not showing my original UA card and the Travelbank one separately.
The rep was wrong, which is all too common with Chase reps. The downgrade to Travelbank UA card is not a new account.