Rail passengers can expect delays travelling from Norwich to London over Christmas as Network Rail begins engineering work on the line.
On December 27 and 28, the service to London Liverpool Street will terminate at Ingatestone, meaning passengers will have to get a replacement bus to Newbury Park Underground station.
People travelling along the same route from January 1 to 3 will also have to take the replacement bus.
Peter Wakefield, chairman of the campaign group Railfuture East Anglia, said: 'There is never a good time to carry out the work, but it has to be done.
'They always tell us that Christmas is one of the quieter times of the year, as people are not going to work. Hopefully it won't be chaos and you will be able to get off your train and onto a bus.'
During the planned works, there will be connections from the Newbury Park station to London Liverpool Street and Stratford. National rail tickets will be accepted on Transport for London services.
The planned engineering work will see Network Rail install new overhead lines between Ilford and Shenfield to improve its reliability.
It is part of a much bigger £150m project involving work on the Greater Anglia, Great Western, Southeastern and Brighton mainlines.
National Rail said it would aim to keep disruption to a minimum.
Are you campaigning to improve rail services? Call Luke Powell on 01603 772684
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