Yep, several emails back and forth but no joy - after initial 'unfortunately we cannot readd the point in this occasion' got a bit more back from them when I suggested it came across they were insinuating I was lying, but alas still a point short!
"We fully understand the commitment and cost involved in following the team away, especially for a ninth trip this season, and we do not question that dedication.
However, when there is a discrepancy of this nature, we are required to rely on the official attendance and scan data provided to us by Arsenal FC. The visiting club controls the stadium entry systems and provides the verified post-match reports, and we have to base any decisions on that official information.
In terms of what you can do going forward, unfortunately there isn’t a specific additional action we can formally recommend (such as rescanning or recording at the turnstile), as we would still ultimately be bound by the host club’s official scan report. That said, if you ever notice an issue at the turnstile — for example, if it doesn’t clearly confirm entry — we would advise raising it immediately with the nearest steward or ticket office on the day so it can be checked and logged there and then.
We completely appreciate how frustrating this situation is, particularly when you know you were present. While we must rely on the data supplied by the host club, please be assured this is not about questioning your honesty but about following the official reporting process we are governed by."