Well why would they have to? If they had the body panels of an original design, but needed to test new internals, what's wrong with using the old? Everyone seems to assume Tesla created something NEW.
^^This^^. EM/TM seems to want to keep this reveal very secretive. We have seen this (or similar) beta vehicles several times and a model S now with sensors on it pulling a trailer. IMO, they are doing lots of street testing on many components that have little to do with the final appearance. BUT....My wife would tell you I am seldom right (even though I think I am!):wink: