If I'm looking to change metal and routing (currently booked on PDX-SFO-PHL, want to leave several hours earlier on PDX-IAH-PHL), my understanding is that I have to do it at the airport -- do I make the request at the check-in desk with UA, which is the ticketing carrier and how I'm currently scheduled to fly? Or does it not matter if I request the change at a RCC/PC?
At SAN, I tried to change from SAN-IAD-PHL (UA) to SAN-EWR-PHL (CO) earlier this week due to the impending storms out east, but the UA check-in folks said I'd have to pay a hefty change fee regardless of status. The agent even said that a GS (which I'm obviously not) would have to pay the same fees.