I'm new to this forum, but not to the subject. (More about ME in a bit.)
Most fora I frequent have an "Office Reception" thread where new users can introduce themselves. I can see this being particularly useful in a field as technical and diverse as Railway Signalling. I may have missed an appropriate thread for the info below; if so, I'd be happy to move it.
Me: I joined BR Research in 1988; within a year, I was developing software and writing data for IECC. Been doing that ever since, for its successor companies AEA Technology and DeltaRail.
I know more than is conducive to sanity about ARS; how it works, what it bases its decisions on, and why it gets things wrong. Similarly I have quite an in-depth knowledge of SSI data, and how it is not so much a signalling system as a safety-critical programming language.
I am also a volunteer signalman on the Bodmin & Wenford Railway, where I was passed-out to operate Bodmin General box in August 2011.