Yes, that would be correct.
On the listed exemptions in paragraph 7 of schedule 1, which is the one that deals with the Benelli M1 and M3 shotguns—which I believe are the ones you're referring to—that list is a closed list. The firearm make and model must be explicitly named in the list in order for it to be exempted, and any new model that comes out would fall within the variant and modified version clause of paragraph 7 and would be prohibited.