Paul Corfield wrote:

* Most strikingly Oyster PAYG "will be accepted on all National Rail
journeys within Greater London on Wednesday and Thursday, just show
your Oyster card at station gate lines". In practice I'm pretty sure
this means that anyone who can flash an Oyster card can travel on NR
services in London.

I'm sure people will simply be waved through.

What about journeys where one has to go through a set of PAYG readers at one
end but not at the other - e.g. Forest Gate (where readers have been
installed but don't appear to be operational) to Liverpool Street (where the
readers are configured for PAYG for Stratford to Liverpool Street), for
travellers substituting Upton Park to central London?

Will these be automatically reversed or will the PAYG user have to chase it
up - especially as they can't easily do so at Forest Gate. (Or could they
nip down to Wanstead Park and touch out on the readers there?)