(Yesterday, 8:02 am)F114TML wrote Wouldn't really say the E6, it was put on to compete with Catch-A-Bus' 6.
Looking at Go North East, pretty sure the X10 didn't exist in 1986 (don't recall seeing it in the May 1986 timetable I've seen) - do please correct if I'm wrong.
There was no fast service (X10) to Middlesbrough, it was the X1 which called at Chester, Durham and Sedgefield....