The future of the East Coast Main Line has been clouded by uncertainty since last year.
In 2005, GNER was awarded a 10-year contract by the Department for Transport to run the service between London and Scotland, ahead of rivals including Virgin and FirstGroup.
But fears for the service grew when it was announced GNER's parent company Sea Containers had filed for bankruptcy protection in the US, where it had crippling financial problems.
This led to speculation the company, which had run the service since 1996, would pull out.
The news led to unions balloting their members for action and passenger groups voicing fears the service could be slashed.
Rival operators lined up to take over the lucrative route, while ministers looked at powers they could use to wrench back control of the franchise.
It was announced on December 15 that the group would be removed as franchise holder. But it was agreed it would continue to run the service under a management contract while the DfT advertised for a new operator.
Last January, the Government said it would take bids and by February a list of four was revealed. But fears remained that planned improvements might be ditched by the new franchise holder.
In response, campaigners launched the East Coast Rail Forum to protect and improve the service. Last month, May the group grilled the four bidders before sending an open letter to ministers voicing demands and fears.
The bids were submitted last week and a decision is awaited.