In message , Brimstone
writes
My earlier figure of 850 feet or 259 meters between platform ends comes from
an LT signalling diagram.

So the other way to do the sums is to guess the platforms are 170m long
(room for 10 cars), which makes the middles 429m apart (and the ends
599m apart, which is exactly where the roads are).

480m doesn't fit that quite so well, unless the platforms are actually
even longer than that. Maybe someone can let us know if the platforms
extend under the roads at all.
--
Roland Perry