Argyll Light Infantry Tank
 

Some information from LAC documents. The "TANK" designation was not added to the badges until at the earliest 1940. Probably later than this date. Regiment applied for new supply of badges with added designation in August 1940.

CAC Formation
 

Bill, the Argyll's request (waiting 4 years after becoming a tank regiment!) for new "tank" badges in August of 1940, is the same month as the formation of the Cdn Armd Corps. Is this just a coincidence or was this a response to the formation of the Corps?

(or perhaps a prudent move by the Argyll's just to wait unit getting access to an actual tank before altering the badge... which also took the same 4 years!? :D )