Originally Posted by
pushmyredbutton
Likely the case here. As an example, UA294 today SFO-DFW is showing a $61 BE fare with a massive $444 upcharge. They aren't really matching a ULCC, though, but it does make sense to capture the last minute non-biz travelers I suppose.
Just came across the same thing on the same route in reverse. DFW-SFO on either Sunday (tomorrow!) or Monday only.
Only available on the first flight out, despite all flights for the day being N9, so I'm guessing the fare rules are limiting it to just this one flight.