Hi epigram,
Thanks for your suggestion
I had actually thought about that a while ago and tried about three different iterations of my name over the course of a few months (i.e. including and removing my middle name; removing Mr from my name which is sometimes appended to my forename by an agent). None of the different iterations seemed to work unfortunately.
My name isn't particularly difficult and is spelt without a middle name on my account. Perhaps I just haven't got the right iteration yet for AA to match up with Cathay yet. I'm not sure what else I can do with amending my name on their booking system, short of actually changing my name.
The mystery shall continue, and I'm glad that I'm probably the only one (or one of the few) with this problem and that it isn't more widespread!
Thanks for your suggestion.
Simon.