Received a response from Tfl – not encouraging I’m afraid:

Thank you for your email of 24 October about your 60+ London Oyster photocard issue on 23 October.
I am sorry for the error code showed when you tried to re enter the station at Wombledon
.
Transport for London (TfL) has an in-built system that prevents fraudulent use of payment cards. The 41 code indicates that your travel pattern was flagged as suspicious, even if it was a genuine mistake. For example, it might occur if you:
• Tap in, change your mind about travelling, tap out, but then decide to go through the gates again.
• Tap in, discover you’re on the wrong platform, tap out, and then tap in on the correct side.
• Experience an error or faulty gate, causing you to tap multiple times
I have taken your feedback on board but at this moment on time, we are unable to amend the system settings, I do apologise.

“Wombledon” was quite an amusing typo though!

Wimbledon is really the only station that this sort of scenario might happen to me due to the 30 minute interval between Thameslink trains. I’d rather leave the station to take a walk and return later than pace the platform for 30 minutes!

Hi Mike,

I didn’t think to check for an error code, sorry, as I immediately moved away from the gate to let others through and sought out an attendant. Perhaps worth mentioning that my card is a 60+ Oyster so maybe the time-out is longer because of its high value? Anyway I just checked my impromptu walk on Google Maps and it was 1.2km so it should have been over 10 minutes but perhaps not as long as I initially estimated. Not got Tfl Go installed, but I will do so and update you.

Steve

Cheers Mike.