Illegal Motion

[Suudy]

The wing on our crew last night was calling illegal motion on the following situation. We got talking about it later and I'm not certain we were doing things right.

A lines up with 8 on the line. The end realizes too many are on the line, so he moves back. While he's moving back, the ball is snapped. Ruling?

This was happening all night. This team was constantly confused on where ot lineup and got flagged multiple times for not being set, multiple guys in motion, and the above situation.