Several variants are actually made above the fighter’s lifespan. These have incorporated the T-45A, that's a two-seat variant also employed by the US Marines, as well as T-45C, an upgraded version which has a glass cockpit and other augments, which currently serves like a product for T-45s however in assistance http://coleyegholm52.jigsy.com/entries/general/An-Unbiased-View-of-american-5th-generation-fighter-jets