It's Rugers company policy to not publish production numbers. As for the comment about not knowing,,, I'd bet it was a true statement. They build guns in a series,, putting serial numbers on a bunch, switch models slightly, and pick up the serialed parts. They do not keep the detailed production numbers easily available to everyone. When building the 22/45,, they could easily build 1000 guns, switch barrel lengths, build another 1000, switch back to the first bbl length, etc.
We rely upon the RENE & members reporting their personal gun info to help us get "close" to production numbers. I doubt that reliable info is available for such a recent gun to the RENE.