Well, the blue Lenham is probably a real one too then. But what is their definition of genuine? He might mean that the project in the advertisement is 100% correct (having all the period bits and pieces, even the Lotus Twin Cam), unlike many of its relatives, which have most likely been equipped with different engines (the blue one has a Ford if I'm not mistaken) and other modern gizmoes. I would be surprised to learn that even unknown, and in fact not historically important Lenhams were replicated. The best thing I could do is try to find some period data of the Lenham cars to dispel all mysteries