There has been a sharp increase in the number of complaints about flight disruption.
The Commission for Aviation Regulation issued its annual report today.
The regulator in charge of enforcing air passenger rights is working to clear a huge backlog of complaints.
In 2017 it was slammed with queries when Ryanair announced a wave of flight cancellations at the end of a busy summer - up to 300 a week.
It had to carry over more than 500 cases into 2018 - but last year was even busier again.
There were 2,319 valid complaints made - a major increase of 56% and by the end of last summer, it had over 1,300 cases waiting to be examined.
It ruled airlines had to pay out in 488 cases - and that cost them a total of €390,000 in compensation and nearly another €70,000 in refunds.
It's planning to beef up its enforcement team in the new year.
But there is a warning it may be swamped with complaints if a no-deal Brexit means complaints under EU law previously handled by British regulators land in its lap.