I assume you are getting a YUP fare on aa.com when you ask for 1st? So far as I know there is no way to get a higher fare if the YUP is available. However, based on my experience last year with one of those you do get 1st class mileage and q-point credit. Also, you are confirmed in 1st so if no changes happen you should get 1st. I recently had a YUP connection through STL vanish with the STL hub and had to be rebooked through DFW. There was clearly no A inventory available but the PLT agent put us in 1st and documented it as a protection from a cancelled flight.