Runway Numbering
Yes, I should have said that the 09/27 style of designator came in in March 1944. I believe from photos of the period that IDs were not painted on runway thresholds until after the war. This was presumably for security purposes and to avoid highlighting runways even more. Not that the Luftwaffe was around much in daylight by then, but there was a very real fear that countermeasures might be taken against the D-day build-up.