Delays building a new bay platform at Stevenage railway station have led bosses to propose replacing services to Hertford North with buses starting in May 2018 – and, separately, Baldock looks set to be left off semi-fast services into London.

The Hertford North proposal, made as part of Great Northern line operator Govia Thameslink’s 2018 timetable consultation, is to free up the existing platforms at Stevenage for extra trains on the main route from London King’s Cross up to King’s Lynn and Cambridge, for which the operator says there is greater passenger demand.

Notes attached to the consultation explain: “We have undertaken a passenger demand review and this clearly shows that the level of demand between Hertford North and Stevenage, whilst important for people who use the service regularly, is lower in comparison with the number of people who would benefit from improved Great Northern and Thameslink services which otherwise would not be able to be provided.”

Figures accompanying this passage indicate that 1,100 passengers per day on average will be affected by the switch to buses, while 104,000 per day will benefit from the improved fast services to London, Cambridge and King’s Lynn.

Apart from a few early morning and late evening trains, there will be rail replacement buses on a permanent basis from Stevenage to both Hertford North and Watton-at-Stone until further notice.

Roger Smith, chairman of the Hitchin Rail User Group, called the proposal a ‘bombshell’.

A Great Northern spokesman told the Comet: “We’d only need to run buses until the new bay, or terminating, platform was finished – but then this is all just a consultation.

“People may say they don’t want the temporary bus service, although that would stop us bringing in the other improvements.”

Meanwhile, Baldock is set to lose semi-fast services to and from London under the plans.

The overall number of trains during off-peak times from Monday to Saturday will stay the same, but Baldock will now be left off the semi-fast trains going via Royston, Letchworth, Hitchin and Stevenage into London.

It will gain a stopping service instead, at the same frequency as Ashwell & Morden – where figures indicate footfall is about a fifth of Baldock’s – leaving passengers with a 56-minute journey from Baldock to London St Pancras, or 47 minutes if they change at Hitchin or Stevenage.

On Sundays, and in the evenings from Monday to Saturday, Baldock will get a single stopping service per hour, with no semi-fast services.

Dr John Dawson, from Baldock, said: “It is most important that everyone who needs to use the semi-fast service from Baldock checks the details in the consultation – the relevant routes are TL6 and TL7 – and completes the survey form.

“If there are not enough passengers complaining, Baldock will be reduced to the same status as Ashwell & Morden.”

Elsewhere, Hitchin and Biggleswade are set to lose their evening peak non-stop trains out of London.

Stevenage will take over the half-hourly service currently enjoyed by Hitchin, and Hitchin and Biggleswade will instead get a half-hourly one-stop service each via Welwyn North and Stevenage respectively. These would supplement off-peak services.

In addition to the stopping services, the proposal is to double the number of semi-fast trains connecting Hitchin and Stevenage to London from two to four per hour.

These would be 12-coach trains running via London St Pancras and London Bridge, with the semi-fast services heading on to Gatwick Airport and either Horsham or Brighton, with stopping services heading to Maidstone East.

A new route to Heathrow Airport could also be opened through an interconnection with Crossrail at Farringdon.

The consultation closes at 5pm on Thursday, December 8. To have your say see thameslinkrailway.com/your-journey/timetable-consultation.

There will also be staff on hand to answer questions at Stevenage station from 6.30am to 9am on Thursday, October 13.