On 12 Apr 2006 02:57:08 -0700, "John B" wrote:

If your Oyster is a PAYG

It is.

you probably don't need to do anything
either. There are certain London Terminals where you'll be charged a
fiver for unresolved PAYG journeys on the National Rail side [snip]
If you have an unresolved PAYG journey from anywhere else, TfL reserve
the right to charge you the maximum fare, but in practice they charge
you the minimum - ie the fare from the zone you touched in to another
station in that zone.

See my other post - this seems to be what has happened.

The only incentive to avoid unresolved PAYG
journeys on LUL is that they do not count towards daily capping.

And this seems to be what might have happened back in October - if it
is the case, and it's the day in London I think it was, then I must
have been able to go through an unmanned barrier at Highbury &
Islington, or possibly went through when the gate was being held open
for someone else. My Oyster was pretty new then (I only gave up the
Travelcard in September) and I may well have forgotten to swipe it.