Do you know how much it would be additionally if I kept the zone 1-5 oyster and brought a ticket for the excess journey?
Thinking about it if the OP has a travelcard held on Oyster and wishes to do a changeover to a paper ticket (whether the Northfleet travelcard or the London Terminals ticket) then this could be problematic as there are probably very few places that could do such a changeover. Can anyone offer any advice on if it is possible and where it could be done.
I suspect a changeover from a season ticket on Oyster to Southeastern's smart cardis a step too far...