After what RavnAir Group called a "malicious" cyberattack on their IT network earlier this month, the company says the impact of the disruption appears to be worse than what they initially reported.

Some RavnAir Alaska flights were canceled due to the Dec. 20 attack. A statement from the airline at the time said it had canceled flights on Dash 8 aircraft and expected more schedule changes.

Ravn said it was working with the FBI, other authorities and a cyber security company to fully restore the systems that were affected, including the Dash 8 maintenance system and its backup.

As of Monday, Dec. 30, Ravn said it may take as long as a month to have all of its systems back to normal. This means additional cancellations and delays are possible for all three of the group's airlines: RavnAir Alaska, PenAir and RavnAir Connect.

Ravn is rebooking passengers on other flights where possible. Anyone affected should call 1-800-866-8394. Passengers not affected by the canceled flights should check in to the airport as usual.

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