The video said that the current version would be considered an SBR... $200 extra dollars and 6 months of wait time for a semi-auto .22 seems pretty ridiculous to me.
Maybe I saw a different video, I thought the guy said they'd be making a pistol version of the MP-40 (which one could go through the process of making into an SBR) and they'd also make a rifle version with a 16" barrel. It wouldn't be out of character for them, because they do the same thing with their MP-5 replica (a pistol and a rifle version). Problem is, an MP-40 with a 16" will look quite inauthentic and goofy, the original barrel is under 10 inches. They can mask the oddness of a long barrel with a faux suppressor on an MP-5 replica, can't really do that with an MP-40 however. Maybe that made them ditch it.