Thanks Cheveron I wondered if it was what a layman would call uncontrolled airspace if that term is used and was not sure of the 'class letter'.
So presumeably the bizjets and Lasham bound airlines are under London control up to some point and they are then just free to proceed as they wish when released from positive control. Given the amount of light aircraft traffic there can be in this area it would seem everyone needs to be pretty much on their toes when transiting the paths the heavier stuff uses to position on the approaches fro BLk FNB or Lasham .I must admit I always found the sight of all the gliders at Lasham mixing with the classic grungy smokey DC8 freighters an interesting sight and Lasham afforded some great views of these beats landing or departing.
Thanks again