It has to do with the fact that the NCAA has nothing to do with the CFP and CFP Committee - 2014 to Present (or its forerunner "The BCS" 1998-2013). The NCAA runs the DIAA Playoff (just as they run all other NCAA Postseason Playoffs in all other NCAA sports at all other NCAA Divisions but DIA Football). It's the NCAA's way of rubbing the P4 Conference's nose in the fact that the NCAA has not sanctioned the CFP (or its forerunner the BCS), but does run the DIAA Playoff just as they run all other NCAA Championships at all other levels but DIA; hence, the change to Football Championship Subdivision ("FCS") and the Football Bowl Subdivision ("FBS") - the NCAA officially went to the new names in 2006.