An ongoing labor dispute between Air Canada and its 10,000 flight attendants is wreaking havoc for half a million travelers and counting.

The labor strike, which began over the weekend, has grounded flights — 700 per day — and left customers stranded, many of them with few options to complete their travels. On Monday, a labor relations board declared the strike illegal and ordered the union to have its members return to work.

But the union said that it would continue to defy the government’s order. “We will not turn our backs on these workers,” said Mark Hancock, the national president of the Canadian Union of Public Employees. “We will do whatever it takes to get them a collective agreement.”

‘You feel like you’re at their mercy’

The airline began rebooking flights ahead of the shutdown, but problems are compounding as cancellations continue. Air Canada estimated on Monday that the labor dispute had resulted in canceled flights for 500,000 passengers, or about 130,000 per day.

Jo-Anne Mazurat-Orlesky, who was on a trip to Toronto with her son when the flight attendants went on strike, was scheduled to fly home to Winnipeg on Sunday, normally a two-and-a-half-hour flight. On Saturday evening she received an email that their flight was canceled. Another email followed several hours later informing her that Air Canada couldn’t rebook her flight.

“They left us in limbo,” said Ms. Mazurat-Orlesky, who had booked her flights through Expedia. “There were no other steps other than to request a refund.”

After learning of the cancellation, she reached out to Expedia, which directed her back to Air Canada. She considered taking the train or making the 1,300-mile drive — some 21 hours, without stops — in a rental car. Both options were more than the cost of her domestic flight. She also showed up at Toronto Pearson International Airport in person on Sunday but couldn’t get her flight rebooked.

“You feel like you’re at their mercy,” she said. “You can’t get a hold of anyone on the phone with the number they give you. You go the airport and they can’t support you. It’s like you’re just waiting for something to happen.”

Airing her frustrations, Ms. Mazurat-Orlesky made a TikTok video at Toronto Pearson on Sunday; another user sent her a customer service number for Air Canada. Air Canada eventually rebooked her flight with WestJet Airlines, the second largest Canadian carrier, departing Tuesday morning.

Refunds and additional expenses

Canadian law requires Air Canada to either rebook passengers on another airline or refund the cost of their flight. But during peak summer travel season, availability on other airlines is limited.

Still, as cancellations mount, many travelers are foregoing refunds and holding out to be rebooked by Air Canada, even if it means waiting several days for an alternative flight.

Among those who weighed their options are Angela Passalacqua and several of her family members, who have been stuck in Sicily since their return flight on Saturday morning was canceled. Ms. Passalacqua, who learned of the cancellation on Friday, said she was unable to get Air Canada on the phone until Sunday. “Every time we called the number, it hung up,” she said.

Two people in Ms. Passalacqua’s family decided to purchase one-way tickets on a United flight at a cost of $1,700 each. (While the airline is required to rebook flights for passengers, customers who purchase their own flights will not be reimbursed, according to the Air Canada website.) The rest of the Passalacqua family will leave Sicily beginning on Thursday on United flights rebooked by Air Canada. In the meantime, the family is stuck paying out of pocket to extend their rental car and their Airbnb — additional expenses that Air Canada is not obligated to cover, since labor actions are considered outside the airline’s control.

“We saved all year for this,” said Ms. Passalacqua, who is a public school teacher in New York. “It’s beautiful here but we’re ready to go home — and we just want our money back.”

Claire Fahy contributed reporting.

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