This may appear to be a very naive question, but perhaps someone could steer me in the right direction. I see from time to time, a release of a new train. But, not being a native of the UK, I cannot find which route(s) to download to run that train. I realise I can use BRR to run the trains on any route. But in the interest of authenticity, where do I look to find, perhaps an index of trains with the actual routes on which they run/ran?