Foul, or Legal?

[rainmaker]

I'm gonna try to describe this play the best I can, I'm just not sure I'll get it across.

First, imagine B1, defending the ball-handler, standing with arms straight up, completely legal. A1 jumps to shoot, B1 jumps a little, goes straight up. There's a little contact as A1 moves her arms and the ball toward the basket, but nowhere near enough contact to call a foul.

Now, imagine the same play, with B1 still completely legal, but there's a lot of contact before A1 goes up. The contact was created by A1, and it's judged incidental. We've all seen this play, haven't we? When A1 goes to shoot, B1 goes up completely in her plane. Both players stay in their own space (the proverbial cones of verticality), and although there's continuous contact all the way up and all the way down, it's all legal, and there's no foul.

Now, here's the questionable play. B1 has complete legal position while A1 is "shaking and baking". As A1 is setting up to shoot, B1 moves her arms backward to about 25 degrees from straight up. Still legal. There's quite a bit of body contact, but it's incidental. As A1 jumps and moves her arms and the ball up and toward the basket (completely legally) staying in her plane, B1 moves her arms quickly back to straight up. There's quite a bit of contact, sudden contact. But B1 never left LGP, and never moved out of her "cone of verticality." B1 didn't flip her hands forward as many hapless guards do in that situation.

The same amount of contact would be completely incidental, if it was continuous as A1 jumped to shoot. But now the contact is sudden, and it's all created by B1, but is it a foul?