(13 Jan 2016, 8:31 pm)South Tyne Lad wrote I'm not a expert on Ashington but I believe there's 2 MAX Spare E400s with one supposedly allocated to the X14 and one Spare.
Them 3 E400s could have been allocated to the X20 with the remaining spare also allocated with 2 of the less reliable B7TLs 7412-15 batch to cover then the remaining B7TL can be sent wherever needed.
Too late now though as them E400s are now Sapphire.
Both spare E400s are spares and don't have set allocations. Only 4659 is the spare vehicle that has a set allocation.
4 vehicles are required for the X20.
7412-5 can't be spares as they are not permitted to do the X18 due to the height of the vehicle.