Air Canada began canceling flights on Thursday, ahead of a possible work stoppage by flight attendants, who issued a 72-hour strike notice, potentially impacting hundreds of thousands of travelers.A complete shutdown of the country’s largest airline threatens to affect approximately 1.3 lakh people daily, A. Mark Nasr, Chief Operations Officer for Air Canada, stated the airline has begun a gradual suspension of Air Canada and Air Canada Rouge operations. “All flights will be paused by Saturday early morning,” he said. Nasr added that this approach will help facilitate an orderly restart “which under the best circumstances will take a full week to complete.” He mentioned that the initial set of cancellations, involving several dozen flights, will impact long-haul overseas flights scheduled to depart Thursday night. “By tomorrow evening we expect to have cancelled flights affecting over 1 lakh customers,” Nasr said. “By the time we get to 1 am on Saturday morning we will be completely grounded.” Nasr said the grounding will affect 25,000 Canadians daily abroad who may become stranded. They anticipate 500 flights to be cancelled by the end of Friday. He further stated that customers whose flights are cancelled will be eligible for a full refund, and the airline has arranged with other Canadian and foreign carriers to provide alternative travel options “to the extent possible.”The Canadian Union of Public Employees (CUPE), representing attendants nationwide, issued a strike notice, leading Air Canada to announce a 72-hour lockout effective August 16. According to the union, 99.7 per cent of its members supported the strike, which will suspend operations from Saturday until a labour agreement is reached. “For the past nine months, we have put forward solid, data-driven proposals on wages and unpaid work, all rooted in fairness and industry standards,” said Wesley Lesosky, President of the Air Canada Component of CUPE. “Air Canada’s response to our proposals makes one thing clear: they are not interested in resolving these critical issues.” The airline stated that eight months of negotiations and an offer to go to arbitration failed to produce a deal.Some flight attendants at the airline’s news conference on Thursday held up signs that read “Unpaid work won’t fly” and “Poverty wages = UnCanadian.”Natasha Stea, who represents flight attendants in Montreal for the union, said she thinks the airline is counting on the government to intervene. Stea said they want a fair and equitable contract.“There is still time. I’m sure if we sat down and talked we could actually get to an agreement,” she said. On August 11, it proposed a 38 per cent pay increase over four years, along with additional benefits and protections, but the union rejected the offer.What to do if your Air Canada flight is cancelledJohn Gradek, who heads McGill University’s aviation management program, said that Canada’s Air Passenger Protection Regulations require airlines to promptly notify passengers of cancellations—via text, voicemail, or email—and outline their options, CBC reported. Typically, Air Canada must cover the cost of rebooking passengers on another airline so they arrive within 48 hours of their original scheduled time. If that’s not possible, or the alternative offered doesn’t meet the passenger’s needs, the airline must issue a refund for the unused ticket value. Expenses for hotels, meals, and other costs incurred while waiting must also be reimbursed—passengers should keep receipts and be prepared to submit them. Canadian North passengers should check how their booking was made: if the Air Canada leg was on a separate ticket, Air Canada is responsible for rebooking; if the journey was booked entirely through Canadian North, that carrier must arrange the replacement flight.