Back in May, I booked a one-way reservation through the Chase portal (extra UR miles) on AA 7/21 MIA-BGR.

I recently found out that I need to change the flight to AA 7/20 MIA-BDL. I canceled my reservation through Chase and now have a travel credit through Chase. It does not show in my AA Wallet.

Since the fare is cheaper, I figured I'd book first class instead of main cabin, which my original reservation was for, and still come out ahead. I've always used AA travel credits like cash (also says so right up there in the wiki). However, Chase is telling me I can't change the fare class. Neither the website "book with credit" tool nor a Chase travel agent will let me do it.

Does this sound right? Has anyone been able to do something like this?