(23 Aug 2014, 9:17 pm)Dan wrote I'll update that tomorrow morning. It would have been the spare for the Derwent Ranger services, hence why it is in white.
Can't actually find any photos of 4978-82 carrying Derwent Ranger branding. 4991 certainly carried that branding, so I suspect 4989/90/92 did too. I can only find the one photo of 4992 carrying "Twenty One" branding too, and none of the others...
Yeah, from what i can remember 4989-4991 all carried Derwent Ranger branding but when they were moved (presumably for the orbit) and replaced by 4978-82 didnt eventhough service 47 was still referred to as the Derwent Ranger whilst these B7RLEs operated the service.