"Steve Fitzgerald" ] wrote in message
...
This applies to LU - I'm not familiar with the 'big trains' to know if
they do the same, although from my limited experience it's not uncommon
for a signal to still show green after a train has passed a signal on
Railtrack.

Depends entirely on the location. On plain line it's not uncommon for there
to be only one track circuit per section, and the train can be quite a
distance past the signal until it goes red. In junction layouts it tends to
be much more immediate. I suspect that there is a standard that says new
installations must have a replacing circuit, BICBW.