(22 Mar 2016, 5:05 pm)Cock Robin wrote Why do they need a better slot between Mbro and Stockton? Would have thought that was the least important part of the route.
I would guess it's being retimed to fit better with the X66/X67 - at present, the 21a leaves Middlesbrough 3 minutes behind an X67 and towards Middlesbrough from Stockton 5 minutes behind the X67.