Aer Lingus customers have been forced to reschedule or cancel transatlantic trips after the airline delayed plans for a year-round service from Shannon Airport to Boston for the second time.
Flights between Shannon and Boston, which were scheduled to begin today, have been delayed until February 4, leaving hundreds of passengers in the lurch.
According to the airline an "unforeseen scheduling delay" with the delivery of a B757 aircraft was to blame.
Plans were initially held up by one week, with the new operations expected to start on January 26.
Since 2011, Aer Lingus has suspended flights from Shannon to Boston and New York for 12 weeks -- between January and March -- to reduce losses.
However, last July the airline announced that its existing Boston and JFK New York flights will operate daily this year.
Up until this month, the airline flew to Boston four times a week and to New York three times a week. An Airbus 330 aircraft was used for these services but in future two smaller Boeing 757 aircraft will serve these routes.
It was expected the Boston route would operate five times a week from today, using a Boeing 757 jet leased from and operated by Dublin-based Air Contractors Ltd and flying daily from March. From the end of March flights to New York will operate five times a week.
In the summer months 12 flights a week will travel to the US from Shannon, compared with last year when the airline operated transatlantic flights seven times per week.
A spokesman for Aer Lingus could not confirm how many passengers have been affected by the delay and said it did not publicise "route-specific load factors".
However, he said the airline had reached out to those affected. "We have been in direct contact with customers affected by these cancellations to offer alternative options," he said.
"These options include changing travel to a later date or flying with Aer Lingus from Dublin to Boston, with ground transportation being provided between Shannon and Dublin.
"Alternatively, customers may choose to cancel their travel plans, in which case they will receive a full refund.
"We regret the inconvenience caused to customers by these cancellations."