In all my years of being interested in and working for the railway, I have never understood the logic or reasons behind unadvertised stops. Now might be a good time to ask those insiders on the group about it because it seems relevant next week.
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Can anybody shed some light on the matter?
I've heard several reasons given. One is that a station is unlit / unstaffed / locked / unsalted and so cannot be used for passengers, but it's useful for people who work for the railways. Another is for timetabled trains that don't always go the same way - useful for staff if the happen to go through "x" and call, but a nightmare is it's a public call the train can't make as it then needs rail replacement road transport which costs much more that the fares .