I'm vaguely aware that the cigs were mainline express and the veps were mainline stoppers. I'm interested in the specific diagrams that these units did, particularly in the NSE era.
I know from memory which sort of trains they worked but I don't have specific diagrams You would be better asking on a forum dealing with real trains
Most of the sets interworked as trains split and joined en-route A lot of info here https://www.bloodandcustard.com/BR-4CIG.html