The move from Eurostar, which operates from the UK to the European Union, including France and Belgium, means passengers can exchange their tickets as many times as they need for no extra fee.
Eurostar passengers have written to the Guardian newspaper consumer affairs section, discussing how they have been unable to book a £520 package deal to France from the UK.
A passenger wrote into the Guardian newspaper, fuming over the treatment of a disabled friend at the hands of the train operator, which runs between London St Pancras and Paris in France.