The play familiarity is tabulated based off your player's knowledge. So it will carry over to the next season only insofar as you retain personnel who have knowledge of that play. Which is to say, if you field an entirely new set of players on offense from one season to the next, then no, that knowledge won't roll over, but if you keep some consistency, their knowledge of your plays will continue to grow over time. If you're ever curious, you can view a player's full knowledge of plays on their individual player page.
Changing OC/DC doesn't affect the plays, however a new HC will come in with a different set of plays they have 'access' to, depending on their style. So you may end up losing many of your core plays and gaining new ones in their stead if you swap out HCs, though any shared plays between the two won't lose familiarity with your players.
Last edited at 9/19/2015 6:54 pm