Notice seen on the 84 bus this morning & is also on the Metroline website:
FROM MONDAY 2 JANUARY 2012, changes will be made to the acceptance of TFL tickets on Route 84, as it will no longer be part of the TFL bus network between New Barnet and Potters Bar.
Transport for London Bus Passes, Travelcards, Oyster Pay As You Go tickets will no longer be accepted on the above section of route, but holders showing these tickets to the driver will be able to obtain a reduced cash fare if travelling in this section of route. Passengers should no longer swipe their tickets on the ticket machine reader.
Further information on this change and on other fare changes also being introduced on this date will be available on our website and on the buses from mid - December.