On 23 Oct, 18:56, Paul Speller wrote:
I want to nip to Greenwich on the way home. I know a Cheap Day Return is
valid for break of journey; I also know that between about 10am and 4pm
it is possible to travel, via the loop line service, from London Bridge
to Crayford via Greenwich, so if I were travelling in the daytime then
presumably I could get off the loop train at Greenwich and get back on
it subsequently to go home.

Yes.

However, I will be travelling in the evening. It is still *possible* to
get to Crayford via the Greenwich line, by changing at Dartford and
travelling back up the line to Crayford - what I like to call the
'virtual loop line' (since the loop line just cuts out the change at
Dartford by turning back on itself up the other line before it gets
there)!

No. Following the Routeing Guide rules, the only permitted route is
direct via Lewisham and Sidcup (the shortest route), or via a direct
train.

Indeed, at times of the week when train services are less frequent, it's
not uncommon for National Rail Enquiries to suggest travelling away from
London and changing at Dartford among its options for getting to London
from Crayford. Does this mean it is a 'valid route' for a Cheap Day
Return?

The journey planner has no official authority to permit a non-
permitted route. Does the red "you need to buy two tickets" warning
appear?

If so, does that mean I can travel to, and break my journey at, Greenwich?

Not unless the train you get off and then on at Greenwich was London-
Crayford, no.

As a final twist, if you do break your journey at a particular station,
are you then obliged to resume your journey at that same station?

No, but it has to be further along a particular permitted route that
covers both legs. Switching from Lewisham to Greenwich wouldn't be
allowed.

(I'm assuming you want to follow the rules strictly. What the rules
say and what you can get away with are very different things)

U

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