The Wythall Museum has three for four BCS battery vehicles in its collection plus quite a few others from other Co-operative societies. including TASCOS, and private companies.
BCS, from memory in the late 1940's, had, in the south of the city and beyond into the Solihull area, horse drawn milk floats and coal carts. I cannot say about their bread deliveries as I only remember small bakery vans and the ubiquitous Scribbans vans.