jon price wrote:In 1934 the Army had very few armoured vehicles, and at the start of WW2 the typical infantry unit only had 13 carriers. Until 1937 there would have been none in a regiment (which in the British Army is actually a battalion). From then to 1939/40 they would have been Bren carriers (not Universal carriers, which is the vehicle you will find as a model kit which only began to be inroduced at that point).
The first experimental armoured and motorised brigades were formed that year [ignoring the, by 1934 disbanded, experimental force of 1927].Generally units were described as battalions for infantry and the Royal Tank Regiment, regiments for former Yeomanry and cavalry units converted to armoured units.
jon price wrote:Although by 1939 all British infantry was technically mechanised (in that motor vehicles were provided for transport) these were a separate unit,
Agreed major movements by road would be carried out by specialist transport units, and there would have been no towed weapons in infantry units in the mid-1930s, but infantry units would still have had some integral motor transport, for mortars and heavy machine guns, and for admin and communication purposes [wireless, collecting stores, providing mobility for regimental officers, etc., plus motor cycles for the reconnaissance platoon.] Admittedly if the unit went on exercises these might well be left behind and others borrowed at the destination.
jon price wrote:so all the officers would fit in a four or six wheel carriage
So far as I know, apart from some minor branches, such stock had gone out of use by the 1930s in favour of bogie vehicles.