Union leaders for Air Canada’s flight attendants said members would return to work after a deal was reached to end a three-day strike that grounded hundreds of flights, hitting around 500,000 customers.

Thousands of passengers are facing another day of travel disruptions as Air Canada flight attendants continue to strike despite a federal return-to-work order.

Air Canada, in a statement issued on Monday afternoon, estimated that the strike, which began early Saturday morning, had resulted in the cancellation of flights for 500,000 passengers.