I'm very interested to see if you had a resolution to this. I'm in exactly the same position. I was 21 tier credits short of concierge but took a return flight with BA on the 18th of March that would have taken me over the line (30 tier credits). This return flight hasn't credited and no amount of calling or submitting forms has helped. I emailed the Aerclub email address as well but this seem to have not delivered. Any other suggestions? I have TA flights booked in May that I would like to try and avail of the upgrades but I'm stuck in limbo right now with no sign of help!