Passes while in punt formation question--

[Suudy]

Now, I understand the casebook indicates the shift does not make somebody eligible.

But what I don't understand is why. Eligibility is determined at the snap, and there can be as many shifts as A wants. And the exception in 7.2.5a says:

Originally Posted by 2007 NFHS Rules 7.2.5b

A player in the game under this exception must assume an initial position on his line of scrimmage between the ends and he remains an ineligible forward-pass receiver during that down unless the pass is touched by B.

The relevant part is "must assume an initial position on his line of scrimmage between the ends."

The question is what is meant by "initial position." I've always thought it meant at the snap. For example, before a shift (assume a scrimmage kick formation in both):

80 23 57 33 58 62 41

After the shift:

23 57 33 58 62 41 80

That is, 80 shifts to the other end of the line.

I understand the casebook says that 23 remains ineligible. But if the "initial position" is established as they first lineup, and they lined up wrong, how can they correct this? What if 80 lined up on the wrong side? Do they all re-huddle then lineup again? Or are they forced to call a timeout?

Thus I think that a fair interpretation would be the position, at the snap, is the "initial position", and determines eligibility.

How did the casebook come up with this interpretation?