As Hertfordshire commuters using the West Anglia rail route between Liverpool Street and Cheshunt start going back to work, they will find new trains awaiting them.
Transport for London (TfL) had originally ordered 45 trains from Bombardier in 2015 for expected delivery in 2018 but extensive software problems around multiple unit working delayed the £260 million contract.
But now Class 710/1 electrical multiple units have finally started arriving. These are replacing the old British Rail Class 315 electrical multiple units which date from 1980/81 manufacture.
In addition six 5-car trains have been ordered for use on the North London Overground service, between London Euston and Watford serving Carpenders Park, Bushey, Watford High Street and Watford Junction.
(based on an article written in International Rail Journal by Keith Fender)