Aer Lingus is expecting to operate its full schedule of flights on Monday after a systems outage resulted in 52 flights being cancelled on Saturday.
The airline said it is communicating directly with customers after complaints about its customer service and communications, as thousands of passengers attempted to rearrange plans.
It said the system outage was caused by a break in connectivity in services from a UK network provider.
The airline apologised to customers after it had to cancel 51 flights to and from Dublin Airport involving UK or European destinations on Saturday.
Footage on social media showed thousands of people queueing outside Terminal 2 on Saturday morning at the airport after digital systems failed.
The airline said that customers affected by the disruption will be able to change their travel plans free of charge.
An Aer Lingus statement said: “Any customer impacted by today’s disruptions will be able apply for a refund or change their travel plans, free of charge through Aerlingus.com, our call centres and our social media channels.
“As systems have now been restored we are contacting customers directly in order to re-accommodate them as efficiently as possible.
“We have made additional customer service agents available to deal with high call volumes – please bear with us as we try to service all customer queries.
“We will also share information regarding customers’ rights.
“Aer Lingus advises customers that its operations for tomorrow are planned to operate as normal.
“Customers are advised to come to the airports at the normal time for their scheduled flight.”
The technical failure affected check-in, boarding and the company website.
It led to the airline having to cancel most flights to and from Dublin Airport to Europe and the UK after 2pm.
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