I live in south London, just north of Croydon. The closest railway station is Selhurst, but in a pinch I can walk to or from East Croydon. This is useful, as East Croydon is an important stop on the main line south, and thus has better services than just about any other station in south London. As well as all stations services, there are express services to both London Bridge and London Victoria, and one can thus get to central London more quickly than from many places that are physically closer to it. Some of the London Bridge services proceed along Thameslink, so one can also get to King's Cross and north London without changing trains. And if one wants to leave the country, there are also very frequent services to Gatwick airport.

So, along my local rail line from Victoria through Clapham Junction, Balham, Norbury, Thornton Heath, Selhurst, East Croydon and beyond, there are two types of service: local services that stop at all stations (including Selhurst), and express services that typically do not stop between Clapham Junction and East Croydon. If I am coming home it is best to get a train that stops at Selhurst, but if I can't manage it and I instead get a train that only stops at East Croydon, I can live with this.

And this is particularly an issue lat at night. For some obscure reason, the line from London Victoria via Selhurst to East Croydon and beyond is one of the very few rail lines in Britain on which a 24 hour service operates. Trains leave Victoria at 2am, 3am, and 4am, meaning that I can get home at any time of night. These are express trains, stopping only at Clapham Junction and East Croydon, and then a few places beyond.

When I first started living here, I often went to some trouble to make the last train home from central London that is scheduled to stop at Selhurst. This leaves Victoria at 12.40am. However, inevitably there were times when I missed this train, or when I missed the previous Selhurst train (which leaves Victoria at around 11.50) and I hopped on an East Croydon train instead.

Which is when I discovered something curious. Although the timetables, departure boards at stations, and PA announcements would declare that the trains stop only at Clapham Junction and East Croydon, these trains would travel rapidly from Clapham Junction to Thornton Heath and would then slow down and stop at Selhurst. People would get off the train at Selhurst, and the trains would proceed on their way.

I experimented further, catching more and more trains that were not supposed to stop at Selhurst. As it happened, I discovered that pretty much every train travelling from Victoria to East Croydon after 10pm stops at Selhurst, regardless of whether the timetable says it does or not. (On one evening a train genuinely did not stop at Selhurst, and the announcer made a point of announcing that "This train does not stop at Selhurst" three or four times prior to the train leaving Victoria, and once again just before it stopped at Clapham Junction). People who live near Selhurst are quite aware of this: sometimes in the early hours of Sunday morning, as many as 30 people will get off the train at its unscheduled Selhurst stop.

What is the reason for this? Well, it's quite simple. South Central (sorry, I mean Southern) has a major depot at Selhurst, and a lot of their staff start and finish their shifts there. The trains stop to allow railway staff who have finished work for the evening to return to their cars / homes / whatever.

Now this is entirely reasonable. However, given that virtually all late trains do in fact stop at Selhurst, can anyone think of a good reason why they don't just advertise this in the timetable? That way new people coming to the area would know at once that they could get home late at night, and would not have to discover the little timetabling secret for themselves.

Or is there some weird regulatory issue at play here. Perhaps if the Selhurst stops became official, permission from seventy six bureaucrats would have to be obtained if the extra stops were ever to be abolished, and if they never exist in the first place then this clearly cannot happen. Or something.