As we parked the Interfacio chartreuse microbus in Olympia’s concrete-lined multi-storey car park last week, we couldn’t help noticing a black and white photograph on the wall with a notice that explained how motor cars had been deposited here since 1937 when the super-modern Art Deco extension was added to the Victorian framework. And so the question formed as we entered this historic site for what could be the last PLASA before Brexit: is the industry about to go into reverse?