Rail passengers have been warned to prepare for “significantly disrupted” travel into the New Year amid a wave of industrial unrest sweeping across the country.The Network Rail statement came as members of the Transport Salaried Staffs’ Association (TSSA) at CrossCountry staged a 24-hour strike from 9pm on Boxing Day as part of a long-running campaign for more rights and a pay increase which addresses the rising cost of living.Network Rail has urged people to plan ahead and check before they depart as "industrial action means rail travel will be significantly disrupted".