(07 Oct 2017, 5:27 pm)JP6004 wrote Same for people heading to shields on a summers day.

That's true, although I don't think it's quite busy enough when it's not really hot to justify double deckers and let's face it, this is Britain, we could possibly only have about 10 really hot days in a year. 

I'm struggling to think of anything other than the Coaster where they could be displaced to (providing they do come off the 21), really of the services that are already double deck operated, it would probably have to be something like maybe be a split between Chester-le-Street and Stanley depots for stuff like Toon Links, 15/15A, 13/X25 and 14/X22 although excluding the 15/15A all those services seem to be a mix of singles and double deckers and most other double decker routes have relatively modern stock (56, 309/310, X1).