CNC plans can be input into a CNC machine, which will automatically cut/route.
CNC machining is a subtractive manufacturing process that involves removing part of a workpiece using instructions from a CAD model to make a product.
I doubt your luthier uses one. He will likely have a router template something like this (maybe not double sided):
Neck Pocket Routing Template for Fender - StewMac
It's just a matter of determining the depth and placement of the neck pocket so the neck works with the bridge you are using.
Yeah, my cousin does some awesome table work ( https://instagram.com/southloft?igshid=NjIwNzIyMDk2Mg== ) and has a CNC at his shop. He wants to make me a bass but needs the plans. I thought a bird would be a fun body to let him go to town on and it'd be easy to get a Fender neck if the pocket was cut right.

