Air Canada has suspended plans to restart operations after the union representing 10,000 flight attendants decided to defy a return-to-work order.

The decision by the union representing the 10,000 workers means that travel chaos will continue for at least a second day. Air Canada said it had suspended its reopening plan until Monday evening.

Air Canada flight attendants returned to the picket line on Sunday defying a government-backed labour board’s order to return to work.The Canadian Union of Public Employees said in a statement that members would remain on strike and invited Air Canada back to the bargaining table.