Thank you for the information. If my memory is correct HRH has served in all three branches of Her Majesty’s Armed Forces in his role as future Commander in Chief. Which is more than one can say of TOTUS unless you count the apologist branch of the Weather Underground.
He is a substantive retired Lieutenant of the Royal Navy, but now holds honourary rank as a General in the Army, Admiral in the Navy, and Air Chief Marshal in the Air Force - and if he'd wanted to show off in Normandy, he'd be fully entitled to wear any of those uniforms. He chose only to wear those decorations to which he is entitled by qualifying service. He was present at the Coronation, and the Jubilees, and at New Zealand's Waitangi celebrations, He does have twelve years qualifying service with the Canadian Forces.