Corporate travel tool is TripActions which I guess books through Expedia. Most of the time it's OK, sometimes it is is a hassle. I typically book through tool and then see if FCM is less than fare difference between Y and F and if it isn't, use the "Modify Flight" tool to rebook into F bucket and just pay the fare difference. For SFO>SEA on 5-Dec the FCM was $380 and the fare difference was $74 -- a no brainer because I can expense it and then I can do SDC for any flight I want and I legit don't know what time I'll be done in SFO so just booked last flight of day.

I called the DM line last night, their systems were down. So I went to "Modify Flight" tool and repriced itinerary in F (went to a D bucket). At confirmation page, however, it showed the right fare difference but showed itinerary in coach with a Q class. Would only let me pick Y seat so I aborted the process. After that, it "downgraded" me from W to Y, which I didn't particularly care about but since I hadn't clicked confirm or purchase thought it was odd.

Waited overnight and tried again but no longer allowed to change ticket. Now inside window and need to pay to get upfront before I may get RU because I want the SDC option more than the UG. Called Medallion line and they offered the $380 FCM at first. I explained repricing was $74 and they agreed to it, but then charged a $50 fee to modify a travel agency ticket

The bug is when I did the Modify Flight and picked F it put me into a Q bucket with an F price and then downgraded me from SU/W despite me confirming or purchasing nothing. And then after I bought the higher fare bucket it still shows the outrageous FCM.