Black Watch Pipers Kilts 1920's-1950

[Nanook]

Hullo all
I am looking for documentation on the type of pleats used in The Black Watch regiment Piper's Kilts around the period of the Second World War.

I'm under the impression that the Black Watch officers where issued kilts with patterns all over the place: Both regimental box and knife line pleated. If we keep to Piper's kilts then knife pleated Royal Stewart..