Thanks guys. It's outstations (most frequent recent ones LGW, HKG, BNE and SIN) where I feel it is has been the case. When it has happened at DXB the upgraded people in front of me did not look like infrequent travelers and maybe they are platinum with gold tags, and maybe they had a miles upgrade request in the system (I didn't know you could do this). It is difficult to know the circumstances, but I think it odd that I have not had one since hitting platinum eight months ago... I do use points to upgrade to first on some flights soon after buying the ticket, maybe these would have upgrades if I had stayed in business.