Mizter T wrote:

I wonder if Mr Salter (the OP) might be so kind as to divulge where
this information came from?

One of those pesky "private and not for publication" type internal
documents, which gives no information as to *why* the stations in
question were chosen, it just says that journeys *ENDING* at said
stations will be subject to a variable maximum journey time, depending
on the zones passed through.

Cheers,

Barry