I'm getting lost in OT. Do you guys still read the rule combinations (3-1-3 and 9-2-1) to provide that in OT, a UC by Team B while in possession cancels a Team B TD, but a UC by Team A while in possession does NOT cancel a Team A TD?
Be sure you are talking about situations in which there is a change of team possession during the down (in extra periods). Without that, it is just penalty enforcement as usual for Team A. i.e., accepted penalties for live-ball fouls cancel a TD but the down is repeated.
But, once there has been a change of team possession, if either team fouls during the down thereafter
and also scores a TD, the TD is canceled and the penalties for fouls other than Personal Fouls and Unsportsmanlike Conduct are declined by rule (i.e., the down is over). If the live-ball fouls are Personal Foul and Unsportsmanlike Conduct, the penalties are carried over to the succeeding spot.