THE CANADIAN PRESS/Darryl Dyck - The Canadian PressAir travellers planning to fly WestJet may be concerned about potential disruptions from a strike, with dozens of flights already cancelled. For summer travellers worried about what this means for their plans, here's what you need to know. The flight attendants represented by the Canadian Union of Public Employees have signalled the intent to go on strike, with negotiations continuing during a 72-hour notice period. Will all WestJet flights be cancelled? Ahead of the potential strike, WestJet has been allowing passengers travelling between July 30 and Aug. 4 to make a one-time change or cancellation with no fees.