For Anglian AV8R: Despite The UK and President Nasser not being the best of friends, as you say, we were able to fly over Egypt whilst ferrying our 105 Sqn Argosies back to the UK for major servicing, but that all came to a sudden end in early February 1967. I was Nav on a crew all ready to do one of these when, with a day or so to go, we heard that Dip Clearance had been withdrawn. We then had to replan and wait for DipClears to be arranged for the CENTO route over Iran and Turkey to Cyprus and, from what I recall, that was the route that had to be used thereafter. I've a feeling that Egyptian assistance to the Yemenis in the general insurgency affecting Aden had been the breaking point in relations.