Originally Posted by
steadyASshegoes
You can change from a 1-stop direct flight to a non-stop, or vice versa, but you cannot change from a connecting flight to a non-stop, or vice versa. Check your flight numbers: if both segments have the same flight number, you will be able to SDC to a nonstop (space permitting).
I did a SDC years ago at the kiosk for a flight to LAS through PDX, where both legs were different flight numbers. It allowed me to get into PDX earlier for $25 but did not give me a non-stop option but my original flight to PDX had a big delay. Wonder if things have changed or if you get better results from talking to a human. I imagine many would pay $25 if they can go non-stop and this would help alleviate things in SFO so they don't get fogged in during a layover.