Trains terminating at Clapham Junction platform 17

[jkwok678]

Sometimes the trains from the west London line terminate on platform 17 instead of the normal platform 1. How comes this happens? Is there a pattern to know whether your train will end at platform 1 or 17? Especially because there are purple readers at platform 1 and 2 and yellow ones at platform 17.

[norbitonflyer]

If 1 and 2 are both occupied, for some reason? (Out of course running, or a failed train) Note that if a train off the South London Line can't access platform 2 because it's already occupied, the signaller has little alternative than to send it to Platform 1. Trains from the West London Line can use Platform 17, but not those from the SLL (in extremis they could use the Windsor Line platforms 3 to 6, I suppose...............)

[slugabed]

Terminators at Platform 17 are,in normal circumstances,Southern Workings,effectively short workings of the Services from the WCML on to the Brighton Line.

[andypurk]

There are also some booked London Overground services into/out of Platform 17. The first train of the day to Stratford is one (empty from Willesden), along with one due between 16:13-16:22 and a couple of terminators around 20:00 (which return empty to Willesden). If the South London Line trains can't use the Clapham Junction platforms, they'll generally turn back at Battersea Park instead.

There also used to be Southern services booked into the old platform 2, but these ceased when the layout was changed to give the two shorter, but separate platforms. The ex-WCML Southern terminators have been much more common during the Covid timetables and through trains are currently only running on Saturday, but with a few trains which would otherwise be stock movements to/from Selhurst.

[jkwok678]

During peak hours, is there enough time for 5/6 trains per hour to get in and out of platform 1 in time for the next train? Would that be why trains would be routed to platform 17?