The company is warning that a new strike called by train drivers’ union ASLEF for Saturday 26 November will cause widespread disruption, with trains on many routes unable to run.
Details are currently being finalised, but the service is likely to consist of:
Trains running only on routes between London Liverpool Street and Norwich, Colchester and Southend Victoria and the Stansted Express service.
No trains on any other routes, including Cambridge to Liverpool Street.
Services will be less frequent than usual and will operate within limited hours, which will be confirmed over the coming days.
Anyone who has booked a ticket to travel on Saturday 26 November will be able to travel either the day before or up to two days afterwards instead, or they can contact their retailer for a refund or to change the date.
Trains not running due to the strike will not be replaced by buses.
First services on Sunday 27 November, will start later than usual as a knock-on effect of the 24-hour strike.
Jamie Burles, Greater Anglia managing director said: “We’re very sorry that once again we must advise people to avoid travelling on our trains, but with our drivers on strike we have no other option.
“We know people will have been planning to go Christmas shopping, visit the Christmas lights in London, go to shows and events or to watch FA Cup matches on Saturday 26 November and that now they will be disappointed.
“We will continue as an industry to carry on talking to ASLEF and other rail unions to try to resolve these disputes, to bring an end to these very disruptive strikes.”