Looking to get my 4 BA segments for requalification. I can book DCA-PHL-LHR return using BA codeshares on AA. Sometimes I find the PHL-LHR on the AA codeshare flight. This is a basic economy fare, although as a BA Gold I can book seats in advance on the BA operated flight. Mainly interested in seat comfort, especially underseat entertainment box infringement and adjustable seat headrests.