One passenger rights expert says if your Air Canada flight has been cancelled, don’t accept a refund. “A refund can be one way for an airline to wash their hands of their obligation to rebook you on another flight,” said Gabor Lukacs, president of Air Passenger Rights.

Air Canada has begun cancelling flights ahead of a planned strike by roughly 10,000 flight attendants this weekend.

If you already have a ticket booked and paid for with Air Canada, then Lukacs says that the Canadian Transportation Agency’s regulations are clear: Air Canada is supposed to foot the bill for a new ticket on another airline.

In the event of a strike, which is classified as outside of an airlines control, large airlines such as Air Canada are still required to book customers a new “reservation for the next available flight that is operated by any carrier,” according to Canada’s Air Passenger Protection Regulations.

“Any carrier means any airline, including, but not limited to, the airlines competitors,” said Lukacs, who adds that the airline must put you on the next available flight towards your final destination, no matter the cost.

“Customers whose flights are cancelled will be notified and they will be eligible for a full refund,” Air Canada said this week in a press release on their website.

Air Canada’s offer of a reimbursement could leave customers out of pocket hundreds, or even thousands of dollars. Lukacs believes the airline is trying to avoid having to rebook customers on a pricier flight with a competitor.