Yeah, I'm not sure how the train ticket would help, unless the DCA flight was delayed before I arrived at the airport and in time that I could take the train to PHL instead and begged the airline to let me on the flight. But in that event at least the Chase Sapphire Reserve travel coverage would kick in and I'd be able to get a hotel room and meals covered for the night—I'm mainly worried about the scenario where I miss my connection but there's no formal delay, meaning that I'm on the hook for my expenses in Philly until the next morning.

Short of buying a different ticket, do I have any other options here? Looks like the only option that gets me into SFO in time to sleep there and avoids a long layover is a routing through DFW--is there any chance AA would just move my ticket over, or at least let me standby? If it makes a difference, I'm AA Plat.