Thanks for having a look at it everyone, I appreciate you trying to help me.
My issue seems to be something quite different to what you are expecting because I can't even get to the thread. Instead I get the following message when I try and view it:
Invalid Thread specified. If you followed a valid link, please notify the administrator
I have tried a couple browsers, including going via my phone to be on via a different ISP. The mobile error message is differently worded to the above, something like "you don't have permission to perform this action ..." But it