We all now seem to agree that vehicles that were ordered, purchsed or issued to British War Office and allocated WO census numbers, and were later given, lent or sold to the AIF. These were alongside other vehicles that came over from Australia. We now need to get to the botttom of the "Given, Lent or Sold". (I won't mention pinched, we only did that to the Yanks
).
Of interest is the pic below from the AWM archives. It shows "AIF L 4515098", a number close to those listed by Shane, yet with the AIF prefix as suggested by Lang. By the look of the cargo, this may also be an Arty vehicle, but not A/T, looks more like 25pdr. Could CAS be "Column, Ammunition Supply"?