Old stock, why is this cut out?

Picked this up a few years ago and never really paid any attention to it until now. Stock is what I believe to be a older SA, both butt plate screw holes are the same size and the only markings visible is a faded serif P in a circle on the grip. What I am wondering about is the cut out that looks something like a clip latch cut out, only on the right front near where the op rod handle would sit. What is the purpose of this cut out?

https://www.milsurps.com/images/impo...100_0321-1.jpg

Not a cut out and if it is that should not be there. The pin holding the Bullet guide, op rod catch and follower arm causes this when people slam the action into the stock and don't notice they have a bad or loose pin. Its common but not as bad as yours. You may want o put a piece of wood in that. Hope this helps. Rick B