Further rail strikes could cause problems for travellers over the next two weeks - but it's still unclear how much of an impact they will have.
Members of the RMT union employed by train operating companies, including Greater Anglia, are planning to walk out on March 16, 18, 30, and April 1 as part of their long-running pay dispute.
But RMT staff employed by Network Rail, including signalling staff, will be working normally after their strikes on those days were called off.
Network Rail has made an improved offer to staff and strikes have been cancelled while RMT members take part in a ballot on whether to accept the deal.
It is the signallers' strikes that have been most damaging for the rail industry over the last nine months - RMT members employed by train operating companies are mainly guards, conductors and station staff.
Train operators have been able to operate most services without them for short periods in the past by using fully-trained managers and supervisory staff to do their jobs.
There is still a chance the train strikes could be called off - the RMT and the Rail Delivery Group which represents the companies have both suggested that talks could be on the cards although nothing has so far been arranged.
Managers at Greater Anglia are monitoring the situation before putting in place any contingency plans for the potential strike days.
Its website urges passengers to check before travel on those days - but even if the action does go ahead there are likely to be more services than have been seen on previous strike days.
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