SamB wrote:
They shouldn't need to read your Oyster - it's of no consequence to
*them* whether or not you have the travelcard on your Oyster, so they
should just sell you the ticket, and then if you don't have the
travelcard you would get done by a ticket inspector. Wherever you go to
buy the extension (anywhere is fine), just ask for a Boundary Zone 2 to
Balham return.



They don't seem to insist on seeing your travelcard when you buy
extension tickets now, presumably because of Oyster, but they always
used to.