DFW 320 is pretty much the most senior NB FO base at American. It’s very commuter friendly—once the commuter holding a line in XYX can hold a line in DFW, they make the switch. Best base for utilizing TTS successfully. FO 737 drivers are notorious for biding 320 after 3-4 years in the guppy because they can hold a decent schedule on the 320 AND can’t hold DFW WB FO. A lot of pilots desire to live and retire in Dallas/Frisco/Fort Worth (They’ll call it DFFW eventually).