That what I love about you frank always ready to see me in the wrong. As I stated right at the start the GPS was a backup up to conventional navigation which was a radial from the DTY VOR and good old looking out the window with a map on my lap. Thye airspace in the GPS is matched to that on the map correctly.
We were not using GPS to skirt around the edge of CAS and for reference the point where I track came closest to the Luton space is where Luton joinst the LTMA and we were already at 1500 by tha point. Our allegded infringement was supposed to have been further up the zone.