On Sat, 12 Aug 2006 08:26:52 +0000 (UTC), Tim Woodall wrote:

I have a Watford Junction to "London Terminals" season ticket that I use
every day to go to Euston.

Very occasionally I want to go south of London, to Brighton maybe 3 times
in a year.

So I ask "Can I use this ticket to Clapham Junction and then just get an
extension?" Yes, says one official at Watford Junction, no says another.
In view of that I decide to buy a full ticket rather than hope that I
can use my Gold Card. I ask the guard on the train whether I could have
used my Gold Card for part of the Journey: "Don't see why not" was the
reply.


Another time I wanted to go to Redhill, so I bought an extension at
Watford Junction. IIRC the extension also said "London Terminals to Redhill".

Something like this came up in uk.railway around a year ago. The
upshot was that the validity of a Watford Junction to London Terminals
ticket covers the following routes:

Watford Junction to Euston (direct);
Watford Junction to Vauxhall (but NOT Waterloo/Victoria), via
Kensington Olympia and Clapham Junction.

So you should have been sold an extension from Clapham Junction
(provided you travel via Kensington Olympia, rather than Euston+Tube).