"Paul Scott" wrote

Aren't Southern also the only TOC that have proactively arranged for the
zone 6 boundary to be changed, to make things a bit simpler in a
particular
area, the Tattenham Corner line IIRC?

They have recently extended Zone 6 from the GLC boundary out to Caterham,
Upper Warlingham, Tattenham Corner and Epsom Downs. Made a pleasant day in
thbe Summer, out to Epsom Downs, walk across the downs to Tattenham Corner,
train to Caterham via Purley, back to Whyteleafe, short walk to Upper
Warlingham, then train back to East Croydon and a Voyager to Kensington
Olympia.

Earlier extensions of Zone 6 have included Hampton Court, Moor Park,
Elstree, and Epping, though IIRC these were all in the first few years of
Travelcards.

Peter