The operator of train services which connect Huntingdonshire to London has promised ‘massive changes’ to its network.
The message comes after passenger services director of Great Northern, Stuart Cheshire, was handed a dossier of evidence of passenger outrage at the firm's services.
The evidence was submitted by MP for Huntingdon Jonathan Djanogly at a meeting with Mr Cheshire to discuss commuters' concerns about the "fall in standards and decline in the service".
"I have given Great Northern an opportunity to explain the issues from their perspective and was pleased to hear that in a number of areas significant changes and improvements are planned," Mr Djanogly told The Hunts Post.
"I will only accept that enough has been done to improve the service when we have a reliable service that meets the needs of local people."
The briefing included travellers branding trains run by Govia Thameslink Railways - which operates the Great Northern franchise - as "completely unacceptable", "infuriating", and "tiring", and some even claimed the service is causing them "anxiety and stress".
Mr Cheshire said: "This was a productive meeting. We listened to Mr Djanogly's concerns and acknowledged that the service must improve. As well as issues with track and signalling, that Network Rail is addressing, we're in the middle of a massive programme of change."
As a part of the improvement programme, the company will be introducing 29 new trains and 116 carriages to the line as well as 86 new drivers, who are currently undergoing training.
The shake-up in the service will also see the company tackle its "poor customer service and communications" with the relaunch of its website as well as the introduction of mobile devices and roving micro-phones to enable staff to update passengers in real time.
Despite the promise from rail bosses Mr Djanogly will still be writing to rail minister Paul Maynard to raise passengers' concerns.
"I will not take Great Northern's reassurances at face value and have asked for a further meeting in January to monitor progress on these issues," he said.
Also as a part of the changes Huntingdon and St Neots could see an increased number of trains passing through stations, which will go from 10 to 12, resulting in four trains per hour from 7-9.59am.
Fears had been raised that two of the current fast high peak trains, from 8-8.59am, would be lost but, according to the company, one of these trains will only be moved to a few minutes later or earlier, dependent on the second stage of the timetable consultation taking place next year.
It is not clear what time the second train will run.
Mr Cheshire added: "The proposed changes to the timetable are just that - proposals - and we're urging people to let us know what they think.
"There will be 20 per cent more trains across the morning peak and they will be spread better which should make the timetable more reliable and, with four trains on a standard hour, they will be easier for passengers to remember."