The reason they are paranoid is because in Japan, they break down the cars by the actual year it was manufactured, and then the model revision.
So your car is a BL, rev. B, Model Year 2005.
See, the problem is, here in America they sell cars within a certain period of the end of the year, and they then call it the next year's model. That's extremely confusing when you think about it, and makes getting the exact part for some cars hard. For instance, we have DBW controllers that need a different wiring harness between pre-2006 models and post 2006 models. But because Subaru would call some 2005 models 2006, they didn't use the newer harness. And it's random which is which. That's why you need a VIN at a dealer to get some parts.