BBC News - Alex Kleiderman
Airlines are expected to announce a series of cancellations to UK summer flights this week aimed at minimising disruption in the peak holiday season.
A government "amnesty" to the rules on airport slots is in place until Friday, allowing airlines to change schedules without facing a potential penalty.
Ministers told carriers to review their plans after chaos in May, blamed on a shortage of airline and airport staff.
British Airways said the move would help provide "certainty" to customers.
The UK's biggest airline, whose services from Heathrow Airport are likely to bear the brunt of this week's cancellations, said the measures would make it "easier to consolidate some of our quieter daily flights to multi-frequency destinations well in advance, and to protect more of our holiday flights".