In message , at 14:34:43
on Thu, 15 Nov 2012, David Cantrell remarked:

If you use your PAYG Oyster card enough in a day that it would have
been cheaper to get a one day travelcard*, then you will only be
charged for a one day travelcard.

And the devil in the detail is "what travelcard". There was a worked
example discussed a few months ago that showed that lots of use in Z1,
plus one excursion to Z2 (or was it Z4) at the end of the day, gets
capped at the higher travelcard figure, which is noticeably more than
the Z1 travelcard plus the extra single fare.

--
Roland Perry