This Saturday is the last time weekend rail travellers from East Anglia will be able to reach London without having to complete part of the journey by bus until after Easter.

Network Rail engineers are moving in to install new overhead lines and track between Stratford and Shenfield in preparation for the launch of Crossrail services on the new Elizabeth Line that is due to open at the end of the year.

On Sunday, and on every weekend until April, there will be a bus replacement service between Ingatestone – and in some cases Witham – and the Central Line’s Newbury Park underground station.

Nearly 8km of new overhead wire will be installed between Ilford and Manor Park, as part of a £250m project to install a new overhead wiring system that automatically adapts to temperature changes.

This follows on from the completion of work to install 10km of overhead wire at Ilford at Christmas. Network Rail says that will result in fewer delays to journeys on the Great Eastern Main Line.

Work also continues on the Crossrail programme to upgrade the mainline and stations between Brentwood and London Liverpool Street in preparation for the opening of the eastern section of the Elizabeth line at the end of 2018.

Meliha Duymaz, Network Rail’s route managing director for Anglia, said: “This work is crucial to improving rail travel in the East Anglia region, to provide more reliable services and improved connections across London.

“The number of people travelling by rail continues to grow and this investment programme forms a key part of our Railway Upgrade Plan to support this demand. I’d like to thank passengers for their patience while we carry out this work.”

Jamie Burles, Greater Anglia managing director, said: “This work is vital for the modernisation of the railway in East Anglia, which both Network Rail and Greater Anglia, are committed to in order to provide a railway fit for future generations.

“We appreciate that engineering work is inconvenient to customers who would rather stay on the train for the whole of their journey. I would like to reassure people that we will make sure they can still complete their journeys, even if part of it is by bus.”