On Mar 9, 5:54*pm, Mizter T wrote:
On Mar 9, 3:58*pm, martin wrote:

It is 20 minutes.
I did this today, largely to see what happens:
Wood Green - Shepherds Bush (Central Line)
pop up to Westfield to collect my now-repaired computer, and return to
the station in under 20 minutes
Shepherds Bush (Overground) - Harringay Green Lanes, touching the pink
validator at Gospel Oak on the way.

The journey history on a tube ticket machine shows up as:
Wood Green - Shepherds Bush (£0)
Wood Green - Uncompleted (£4.30, which is the entry charge for a tube
station)
Gospel Oak - Harringay Green Lanes (£1.30)

[snip]

From what I understand from this group, the system ought to work out
where I've been, and refund me £1.90 in the next couple of days.

What's been termed an 'auto-correction', which is a useful way of
describing it. Do report back on how long this takes.

I got an email on Friday night / Saturday morning telling me that 'due
to an operational issue,' I was due a refund of £6.20, which was
waiting for me at Wood Green.
I have no idea how they arrived at this figure. I'm not complaining,
though!