Unusual 1941 CCM "National" Bicycle (motorbike frame)

Here is an unusual one, a CCM "National" Has anyone heard of this model? It is from 1941, and appears to be all original, including the paint... Has the cotter pin cranks with small bottom bracket. Cranks are stamped "UTILITY"    "BRITISHMADE"
Dark Blue frame, fenders, rims with white pinstripes.