The arrival in Scotland of 27 refurbished High Speed Trains in 2017/18 paves the way for their introduction in June-December 2018.

This is dependent on them being released by First Great Western as electrification is completed between London and Bristol/Oxford. The HSTs will displace Class 170 diesel units on the services from Edinburgh and Glasgow to Stirling, Perth, Dundee, Aberdeen and Inverness.

Before the trains enter service - there will be 14 four-car sets (two Class 43 power cars plus four carriages) and 13 five-car sets (2+5) - they will be fully refurbished with new seats and tables, new floor coverings and carpets, re-coated ceilings, WiFi and power sockets, improved LED lighting, and the exterior slam doors will be replaced by power-operated ones (in line with the PRM-TSI regulations).