More to deal with armoured cars, carriers, halftracks, etc., but a memo was found describing the tactical marks thusly:
There seems to be a variation adopted by some (all?) Canadian units in the form of an inverted letter D on it's side:
http://www.mapleleafup.net/forums/at...1&d=1458513135
Any info on when or why this was done, and was it only typical of Canadian units? Also which formations would have a D squadron (or company) - I can think of Armoured Car regiment, Motor and perhaps MG battalions. Did armoured regiments ever have a 4th squadron during WW2?