(26 Nov 2015, 10:12 pm)S813 FVK wrote After guessing that the bridge in question is after Seaham as deckers can operate service 60 until that point (i know they don't follow the same route), the only railway bridge that i can find on the X7 route is going over the railway just after Spectrum Business Park on the A182. By this time, the 60 has gone up Hill Crescent which is the location of the low bridge which stops the 60 from being allocated deckers.
EDIT: It goes under a railway bridge on the B1287 just before the roundabout where it goes onto the A1018 - guessing that this is the bridge in question. An alternative route allowing deckers would be to reroute it along the A1018 then along the B1285 and Lord Byrons Walk before rejoining the B1287 as normal where Tonia's cafe is (would normally follow the road around as opposed to turning off at that junction).
That's why the old northern X96 service was all single decker allocation with the coaches during the day and mini mercs on evenings