Is this the one?

[Welpe]

Originally Posted by Bishopcolle

If B intercepts the ball in A's frontcourt and throws a bullet towards B's frontcourt for a break-away, but A-1 leaps high into the air a step in front of the division line (in A's frontcourt), and then falls or lands in A's backcourt from the momentum of the leap, isn't that a backcourt violation on A?

You don't make it clear when the A player gains possession of the ball, but if it is when he is airborne, then no, it is not a violation. An airborne player of the team not in possession is allowed to jump from the front court, catch the ball in the air and land in the backcourt. 9-9-3 is your reference.

Either way, A-1, regardless of where he catches the ball, is the last to touch it in A's frontcourt

Is he though? I don't think he is as he is located in the backcourt. The touch occurs in the backcourt.