When departing Sunderland (bound for Middlesbrough), the destination read, "X7 Peterlee for Middlesbrough". When departing Peterlee (bound for Middlesbrough), the destination read "X7 Middlesbrough via xxx - xxx -xxx".
On the opposite direction, bound for Sunderland, just the opposite.
Although I must admit I have seen photos of the X7 carrying the destination, "X7 Middlesbrough via xxx - xxx - xxx" upon departing Middlesbrough, I believe this was a rookie mistake from the drivers with it being the first day of the service's operation. I think that they would have typed in the wrong code, not knowing it had to be split up.
RE: Go North East