Legal or not???

[PGCougar]

Was watching a heated AAU game last night and observed some interesting post play. Although there's another thread about illegal screens in the pick & roll, this question is about screens off the ball. Here's the situation:

A1 is a very wide and somewhat large post player. B1 played behind the post on D. Every time ball went to wing or corner, A1 calls for the ball with one or both arms high, but was actually moving around making sure she maintained contact with B1, keeping B1 behind her in the paint, while the wing player A2 slashed in and pulled up for a short range jumper in front of A who was in effect "screening" the post defender. Play was run repeatedly and A1 never actually got the ball once. Jump shot after jump shot. Lots of jawboning by Coach of B but no calls were ever made.

Coach of B makes an adjustment having B1 front A1. Now the lob goes in to A1, and it's evident that A1 doesn't have any skill to finish well. The adjustment worked in this case because A1 couldn't finish, but it made me really think about the post play a bit more.

Question: If A1 was calling for the ball but constantly moving around the blocks, pinning her defender (while moving) is this considered an illegal screen? Should this have been called? What are you as officials looking for in this case?

Sorry for the long set-up of the question.