Maybe the issues surrounding reliability on the X9/10 is to introduce a more fluid network of vehicles.
This could be through interworking with a less demanding route at one end.
Or, by having the vehicles on a shared route where they aren't allocated to the X9/10 on a daily basis.
If they're on the route half the week, in theory that will double their lifespan - based on a 3 day allocation on the X9/10 and 3 days on a less demanding route.
RE: Go North East: Latest News & Discussion - September 2016
'Illegitimis non carborundum'