Is there a typo in case 7.1.5? It says it is encroachment for B to be in or beyond the neutral zone giving defensive signals.

This is where the umpire can control B.
 

After the referee declares the ball ready for play, B cannot be in the neutral zone or on A's side of the neutral zone giving defensive signals.

This is where the umpire can tell B: stay on your side of the neutral zone!

Also, this is one of the trick questions on the NF football exams. The question goes something like this: B cannot encroach until the ball is marked ready for play AND the center places his hand(s) on the ball. The correct answer is false.

A's side is behind the neutral zone, correct?

I would guess that from B's perspective, beyond the NZ is on A's side of the NZ and behind is on B's side. Just the opposite for A.

That's what I hate about the test questions, you never want to assume, "Well, they must mean..." because that may <i>be</i> the question (the out of place word, that is).

Unfortunately, the Federation doesn't explicitly define "behind" or "beyond" either for the purpose of the neutral zone or the basic spot. I guess they think it's intuitive.