Clarification
Thanks for all your replies!
Just to clear this up, back in 2008 I was successful at OASC and was provisionally accepted pending the medical history checks. That's where I fell down. Thanks to a chest infection back in 2007 the GP wrote in my records there was a slight wheeze in one of my lungs which disappeared and never came back. This was enough to bar me for 4 years. I was prescribed an inhaler but fortunately managed to appeal that as irrelevant and a mis-prescription. I then got a letter from the president of the medical board stating that I would not be eligible for ground-crew (I applied for Admin, now Personnel support) until May 2011. I was inquiring as to whether this "4 years clear" policy had changed in the last 2 years. Thanks for all the feedback though! Just have to go through the rig-ma-roll of the applications process again at the end of the year!