Mizter T wrote:

lots of useful information, snipped - thanks for that

[2] The list of stations between which cross-London Tube transfer is
valid is available on this National Rail webpage - click on "show
Station List" to, er, see the list:
http://www.nationalrail.co.uk/times_fares/london/

I wonder if they're going to add Woolwich Arsenal to the list? If
Lewisham is on there, I can't see any reason why WA can't be? West
Horndon to Plumstead via West Ham, the Jubilee line to Canning Town and
the DLR to Woolwich would be quicker?