I believe that the designation of GR3 resulted from the change to the Pegasus 103 engine, not the change to the nose shape. From what I can recall, there were a number of airframes with the new engine which did not gain the new nose shape for some time, and I assume that this is the case with XW765 (if my memory isn't failing me completely). There will be some Ppruners who will know for certain, though, who'll hopefully be along shortly...