On 17 Sep, 15:35, Paul Weaver wrote:

(snip)

And a rail-only season ticket MKC-London won't be valid south of
Harrow, without buying a Willesden-Clapham ticket before joining the
train.


But would one actually need a Harrow & Wealdstone to Clapham Junction
ticket? This particular case does seem somewhat ambiguous - we know
that it's legit to combine a season ticket with a normal single or
return even when a train doesn't stop at a particular station, the
question here is whether the MKC to East Croydon via WLL service even
counts for these purposes as passing through Willesden Junction - the
geographic is that it doesn't pass through any platforms at Willesden
Junction and in fact uses the lines on the south side of the WCML
which are the furthest away from WJ station.

If one was to change at H&W onto a DC lines train to Willesden
Junction, then change there on to a WLL train to Clapham Junction then
this would unambiguously only require a WJ to CJ ticket - but I'm
interested in what the situation is with regards to the through
Southern service that doesn't stop or indeed even go through Willesden
Junction station.