Planned engineering works by Network Rail will affect Thameslink and Great Northern services in February, with four days of line closures.

Network Rail teams have already completed two weekends of upgrades as part of the billion-pound East Coast Digital Programme (ECDP).

Further engineering work between King’s Cross and Peterborough will close a section of the East Coast Main Line from Saturday, February 17 to Tuesday, February 20.

The ECDP will allow digital in-cab signalling to operate on the East Coast Main Line in 2025.

The first section of the new digital signalling system between Welwyn and Hitchin will be installed during February's engineering works, paving the way for train testing in the next phase of the programme.

Between February 17 and 20, no Thameslink or Great Northern trains will operate between Stevenage and Hertford North, Potters Bar and Peterborough, and Potters Bar and Royston.

Additionally, on February 18 only, there will be no trains between Alexandra Palace and Potters Bar.

An amended train service will run between:
•    King’s Cross and Potters Bar (February 17, 19, 20. On February 18, this will run to/from King’s Cross and Alexandra Palace)
•    Moorgate and Potters Bar (February 17, 19, 20. On February 18, this will run to/from Moorgate and Alexandra Palace)
•    Moorgate, Alexandra Palace and Hertford North
•    Royston and Kings Lynn

An extremely limited rail replacement bus service will run across the four days between:
•    Peterborough and Bedford via Huntingdon and St Neots
•    Peterborough and Hitchin
•    Royston and Hitchin
•    Stevenage and Luton Airport Parkway via Hitchin
•    St Albans and Stevenage via Welwyn Garden City
•    Potters Bar and Hitchin
•    Hertford North and Stevenage Hitchin and Peterborough (calling at all stations)

In addition to the above, on February 18 only, there will be a rail replacement bus service between:
•    Alexandra Palace and Welwyn Garden City via Cockfosters
•    Potters Bar and Cockfosters via Hadley Wood

Weekend work mostly additional to the ECDP will also see changes to services on February 10 and 11. Over this weekend, engineers will be working in the Peterborough area to replace switches and crossings, which allow trains to move between tracks.

Buses will replace Thameslink trains between Peterborough and Huntingdon.

Ricky Barsby, head of access and integration for ECDP, said: "This is a huge milestone for the project. Commissioning the Welwyn to Hitchin stretch will allow us to start testing the new system with trains and is testament to the incredible hard work and dedication of our engineers over the last year.

"We know this extended work, especially working over a Monday and Tuesday, will cause disruption to passengers and we are very sorry for that. Our engineers will be working around the clock to complete this work.

"We would encourage all passengers to check their journey via National Rail Enquiries before they travel, and want to thank them for their patience and understanding."

Jenny Saunders, customer services director at Govia Thameslink Railway, added: "We are very sorry for the disruption this will cause our Great Northern and Thameslink customers. Unusually, this work straddles two working days in addition to a weekend, so please plan ahead and check your journey to see how it is affected.

"The extremely limited rail replacement bus service is likely to be very busy over this four-day period, so we are encouraging customers to travel later in the week if they can.

"In particular, we’d urge people to work from home on February 19 and 20, if possible, to keep replacement bus services free for key workers."