Originally Posted by CPH-Flyer

You can upgrade with miles from JMB, not with any other OW programs. There is no cash upgrade offers to F. You could of course reprice your ticket in to F but that is probably not what you meant.

DFW does not have F. So if you want to be able to do a miles upgrade, LAX, SFO, ORD, JFK are the gateways at the moment.