I'm forced to use Concur for all my work-related travel bookings. It's awful. I'm trying to book a trip to Tel Aviv on UA in a fare class that will allow me to use GPUs to upgrade to C. No matter what, the return always comes up in S or T class which are not eligible, even though the lowest fare on united.com shows an M fare, no S or T. The "show other fares" button rarely brings up anything besides a $3800 B fare which I can't purchase without setting off all kinds of alarms.

Any way to trick this thing?