Having left King's Cross some four miles south of this location on time 46233 'Duchess of Sutherland' has been leading The Lindum Fayre charter on the fast line. However, as can be seen in this photograph control have lost their nerve and are moving it to the slow line here at Alexandra Palace. However, the cross over is a flying junction and the charter is still going at a fair rate of knots as it passes.
There is an audio recording of this event on my youtube channel, see....
https://youtu.be/6UPgNRBff3g