(04 Jun 2014, 8:30 pm)Dan wrote I don't think any of the photographs I showed above were taken in winter-time, most being in the summer months but with one or two around February/March too iirc.
The top photo of the Compass Cadet was November, but it had been fairly pleasant if my memory serves.
I'm not defending a bus looking like that on the exterior, but perhaps it's more visible on a white bus than it is on the grey examples you posted? Another two you've taken of white buses:
Exterior shot of Go North East's 563, Transbus MPD/Transbus Mini Pointer by danielgrahamm, on Flickr
Exterior shot of A-LINE's T601JBA, Dennis Dart SLF/Marshall Capital by danielgrahamm, on Flickr