DALLAS (CBS/AP) — American Airlines and its pilot union have come to an agreement to staff all flights over the holiday season.

The news comes after the airliner mistakenly scheduled vacation for 15,000 pilots.

An airline spokesperson told Yahoo Finance that the scheduling debacle was due to a clerical issue, not a computer glitch as initially reported.

The pilots’ union had said that more than 15,000 flights lacked a captain, co-pilot or both when a problem was discovered in the company’s scheduling system. Pilots were allowed to take vacation days in the last two weeks of December even if there wasn’t another pilot available to operate the flight.

American has declined to say how many flights were originally affected, but it did not dispute the union’s initial figure. The airline has about 15,000 pilots and roughly 200,000 flights scheduled during December.

News of the scheduling glitch had caused some passengers to worry that their holiday flights could be canceled for lack of pilots.

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