Is there any reason you can't use a valid ticket at that airport, on that day, to get through security? I'm pretty sure I've done it before - accidentally going to the wrong terminal as the TSA agent only checked name/date.

Heck, my wife got to the gate last week for her PIT-DCA flight with her return, same-day BP.

The downside of course is needing to transfer between terminals and go through security again, and the time required to do that before your flight.