Ok I figured I would give an update on that.
The GA said it was no problem and they would be happy to put me on the DL. They ended up with 8 no-shows so no need for volunteers.
Interesting note tho on the return today I was supposed to go back through ORD but they canceled the flight (weather is pretty bad right now). They offered me a seat through IAD but mentioned my connection was overbooked too.
Asked if they could just put me on the DL direct and they booked me into J on DL, (original flight was UA upgraded from Y).