Originally Posted by
jfidler
First thing to check is the booking class if you upgrade. I've done upgrades on UA from Y to C and the booking class was basically like an award ticket = no miles earned at all.
Correct me if I'm wrong, but aren't mileage earnings for upgraded tickets based on the original ticket class? That has been my experience with *A upgrades so far.
In response to OP's original question, I believe it is possible. I often book Y/B flights on BR, process the SAUA using Aeroplan miles, and credit the flight to UA. I would typically double check that the FFP you want to credit the miles to is printed on your boarding pass.