Misbehaving validator(s) at Highbury & Islington

So, forum user Michael Tsang reported an issue with a journey from Willesden Green to Highbury & Islington.  The route he took was Jubilee line to West Hampstead, Mildmay line to Highbury & Islington and touched out on the Victoria line northbound platform before taking a Great Northern train which he already had a ticket for.  The validators on the Victoria line platforms at Highbury are there specifically for people starting or ending a PAYG journey with onward travel via Great Northern to/from somewhere beyond the PAYG area.  The assumption is that the PAYG journey will likely be using the Victoria line, but I see no reason why that should be the case. To enable me to follow this through personally I decided to try and recreate the journey, and lo and behold the same thing happened. Here is my journey history:

At first glance this looks like a journey that has taken too long.  If the exit at Highbury had been at the gate it might have described it as an unstarted journey ([No touch-in] to Highbury & Islington).  However, because a validator cannot determine which way you are going it will default to entry unless you have a valid open journey.  There are two things wrong with this assumption though – firstly it had nowhere near exceeded the maximum journey time (41 minutes where 100 are allowed); and secondly the summary line should have read Highbury & Islington to [No touch-out].

I called up the helpdesk the next day and explained what had happened.  The helpful person agreed with my observations, processed a refund, and raised an issue for the technical team with a request that I get told what the outcome was.  I’ll admit that I’d forgotten about this when I received a call this afternoon.  We went through what had happened and it transpired that some checks had been made with the validators and no fault was found.  Today’s person agreed to put it back for further investigation and said they would process a refund.  I said that I was sure that I’d already had the refund so we left it at that.  They did seem to be happy to admit that sometimes the Oyster system goes wrong, which is cold comfort if as a result of it going wrong a customer is penalty fared or reported for prosecution.

This evening I went to try a different scenario which was a simple Victoria line journey from Kings Cross St Pancras to Highbury & Islington and touch out on the platform.  This worked exactly as expected (almost – but more on that later on).  I’ve got some more variations which I hope to try out in the coming days, so watch this space.