Fig 4 - Tracking the movement of the train
In Fig 4 above, train 7752 is now occupying track circuits 103, 105 and 107. The distortion of the apparent train length is even more evident now. Remember that, as soon as the first pair of wheels of the train enters the section, the track circuit detects them and switches to "occupied", hence the whole of 103 shows red.
Fig 5 - The train has released the points
Train 7752 (Fig 5 above) has now moved on some distance and the signalman’s view of things has changed to match. The train is clear of the