OWE looking to fly MSY-SEA on AS. I started a booking online and input my BA FF number (which is where my OWE status lies)—unfortunately, in contrast with what happens when I book on AA, I don’t seem to be able to choose premium seats without paying extra. I can book myself into MCE on AA for free as a OWE; is this perk not available on AS? What benefits do I get in general on AS?