An interesting question
I am one of a small team based on this site currently researching the British presence in north west Germany in 1945-48
The Control Commission Germany (CCG) provided the Civil Servant element of the British Military Government and were responsible for the control of all key economic political and infrastructure matters pending the creation of a genuine democratic system of government to replace the previous Nazi systems.
I believe that any order for the manufacture of large numbers of buses would have had to had CCG approval though they would not necessarily have been the users.
Rail was the preferred system of long distance passenger traffic, both military and civilian in the immediate post war period. The buses therefore would have been used on relatively short distances.
There are two possible options.
One. Some of the buses could have been ordered to provide a military transport system fo British troops and later their families in the garrison towns.
Two The orders could have been placed to replace or enhance war damaged civilian owned buses to recreate the nucleus of an efficient and effective local bus service for the German civilian population throughout the British Zone.
It would be helpful if you could post a photo of one of the CCG buses, the team might be able to give further information on possible usage.