The Danish cancellations primarily affect flights between Copenhagen and Charleroi near Belgian capital Brussels, where 40 flights have been cancelled on Mondays, Tuesdays, Fridays and Saturdays from September 25th to October 28th.

Flights on Thursdays between Copenhagen and Bergamo, northeast of Milan, have also been cancelled in the same period.

Other cancellations between September 20th and 24th affect Copenhagen, Billund and Aalborg airports.

The Irish low-budget airline announced on Friday last week that it was cancelling 2,000 flights over a six-week period to enable pilots to use contracted holiday.

Increases in holiday allowances for pilots and cabin staff have contributed to the backlog in staff leave, reports The Guardian.

After initially not announcing which flights would be affected by the cancellations, Ryanair was overwhelmed with requests for information by passengers, which appears to have led to the announcement on Sunday of cancelled flights up to and including September 20th, writes check-in.dk, which estimates up to 10,000 passengers traveling through Denmark will be affected by the cancellations.

This isn't good enough. Release a list now of all the flights you plan to cancel so your paying customers can make alternative arrangements!

— Chloe Morrison (@_chloemo) September 16, 2017

The list was extended on Monday to cover all cancelled flights up to October 28th. All cancelled flights are now listed on Ryanair's website.

Her er alle Ryanairs danske aflysninger – https://t.co/idMOuWgWCC pic.twitter.com/TBOYASmsbt

— CHECK-IN.dk (@checkindk) September 18, 2017

Ten of Ryanair’s 400 aircraft will be grounded until October 31st as a result of the issue.

The airline’s chief executive Michael O’Leary apologised “unreservedly” for “a mess of our own making” at a press conference in Dublin on Monday, according to The Guardian’s report.

O’Leary also said that he regretted the way in which the cancellations were initially handled by the airline.

“We did not focus on the concern we were causing to the 18 million passengers flying with us over the next six weeks,” he said.

On its website, Ryanair gives passengers hit by cancellations the option of applying for a refund or changing their flight, subject to availability.

But O’Leary added that secondary losses to customers, such as cancelled hotel or rental car bookings, would not be covered by the airline, nor would bills for rebooked flights with other airlines be footed.

“We will not pay for flights on other airlines. We cannot afford to pay the high costs of our competitors,” the CEO said according to The Guardian’s report.

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