On Fri, 1 May 2009 07:36:10 -0700 (PDT), Mizter T wrote:

One of those pesky "private and not for publication" type internal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.

Thanks Barry. So it only applies to journeys ending at the
aforementioned stations, eh... I presume it would also inevitably
apply to people making out-of-station interchanges (OSIs) between
these two stations as well, as the Oyster reader on the gate obviously
can't mind read what the passenger's intentions are.

Yes, I think that would have to be the case - e.g. so someone exiting
at Hanger Lane for an OSI to Park Royal would get the time limit
adjusted (presumably adding extra time) for the *whole* journey, not
just the first leg. I can't see why else the list would consist mostly
of OSI stations.

The list also suggests that this will apply to intermediate
validators, as it includes stations that have no apparent significance
other than being interchanges at the tip of a 'V' (i.e. where you are
heading out of the zones and then can turn back so you are heading
inwards, or vice versa). This suggests that, for example:

- Travellers from Northwood to Heathrow will have to touch
inetrmediate validators (on the platform/footbridge) at Rayners Lane
and Acton Town, to extend their time limit and so avoid exceeding the
maximum time for a Z3456 journey

- Travellers from Upminster Bridge to Epping will have to touch at
West Ham or Mile End for a time extension to avoid overrunning the
Z(2)3456 limit

- Travellers from Heathrow to Wimbledon Park will have to touch at
Earls Court to avoid overrunning the Z23456 limit.

Similarly for Gospel Oak to Barons Court (Z23, touching at
Gunnersbury) and Upper Holloway to Bromley-By-Bow (Z234, touching at
Barking).

Of course, since the (reduced) variable limits aren't applied at the
destination (Bromley-By-Bow in the last example), the time extensions
aren't actually required yet - but presumably this is the first phase
in a phased introduction.

That doesn't explain all of the stations on the list, though - I'm
still mystified as to why odd-ones-out like Bond Street are included.
Perhaps it's just as a trial as part of the phased introduction.