If an opponent of the scoring team commits a foul (other than unsportsmanlike conduct on [sic] a nonplayer foul) during a down in which a touchdown is scored and there was not a change of possession during the down, A may accept the results of the play and choose enforcement of the penalty:
a. On the try, or
b. On the subsequent kickoff."
Where does "there was not a change of possession during the down" come into play in the play with an interception and a facemask against the scoring team? We have been doing it that way but as I read this it brought this question to my mind.