All will become clear in time. I do note the careful qualification in
the document that Oyster PAYG is "due" to be introduced across NR in
London in September 2009. I think I might only entirely believe it
when I see it, and indeed can 'touch' it!
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[1] This map shows which NR routes in London currently accept Oyster
PAYG:http://www.tfl.gov.uk/assets/downloa...ayg-on-nationa...
I note that the Heathrow branch is now included on this map, though it
is grayed out at present.