Exascot
There is no way the valet would have got it wrong, these guys are very switched on regarding military dress.
A few years ago I met HRH at a Reserve Forces display; he was in an RAF uniform. As he approached me I noticed that instead of the light blue shirt, he was wearing one which was actually very small dark blue and white checks. From a distance you couldn't tell, but I had great difficulty in concentrating on what he was saying to me after that.
cc