Twenty-two flights a week to and from Dublin have been cancelled by Ryanair.
Yesterday, the airline announced that it was grounding 18,000 flights from its winter schedule affecting up to 400,000 passengers.
It has emerged today that passengers intending to travel from Dublin will be affected.
Three flights departing on Mondays have been cancelled including Dublin to Birmingham (flight no. FR 664), Paris Beauvais (FR 22) and Barcelona (FR 3977).
A Thursday flight to and from Bucharest has been cancelled (FR 7346 and 7347)
Five outbound flights from Dublin on Fridays have been suspended: to Birmingham, Paris Beauvais, Barcelona, Madrid (FR 7156) and Warsaw Modlin (FR 4543).
Two outbound flights from Dublin Airport on Sundays, to Birmingham and Krakow (FR 1901), and return flights from the same airports (FR 665 and 1902), have also been suspended.
These cancellations relate to individual flights.
Ryanair has five daily flights to Birmingham on Mondays and it is one flight that is being cancelled. The other four will operate as normal.
The office of the Commission for Aviation Regulation Ireland says it has received a high volume of calls and up to 400 emails a week in relation to the cancellation of Ryanair flights.
Speaking on RTÉ's Today with Seán O'Rourke, Cathy Mannion said Ryanair passengers should have been given more information about their ability to use alternative airlines and/or modes of transport after their flights were cancelled.
She said the commission was not in a position to force the airline to provide more information to passengers about rerouting options.
The commission, she said, has been in discussions with Ryanair and said that the airline has now agreed to inform passengers about such alternative travel options, such as another airline or even a ferry.
She advised that the best way to approach the claims process is to keep all receipts, and allow Ryanair 28 days to respond to a claim.
Customers, she said, can then bring their issue to the Commission for Aviation Regulation Ireland if they are still unsatisfied.