The CAA said it is seeking answers from BA after after wrongly telling passengers their flights were cancelled due to a pilots strike.
Pilots at the airline are due to walk out on September 9, 10 and 27 but customers with tickets booked for other days were told on Saturday that flights were cancelled.
BA later owned up to mishap and said it will refund those who booked alternatives.
CAA director Richard Stephenson said: “We have been in contact with the airline to determine what has happened and are seeking an explanation to confirm how it complied with its re-routing obligations to consumers.
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“Passengers who have seen their flights cancelled should be offered the choice of reimbursement for cancelled flights, alternate travel arrangements under comparable conditions at the earliest opportunity which includes flights on other airlines, or a new flight at a later date at the passenger’s convenience.
“We also expect airlines to proactively provide passengers with information about their rights when flights are cancelled.”
BA said it was dealing with a backlog of 40,000 customer calls.
Customers took to social media to voice their anger and frustration, with many complaining abut waiting “hours” to get through to the airline’s customer services and others saying they kept being cut off.
Some received two conflicting emails on Saturday. The first told them their flights had been cancelled and that they should rebook or seek refunds. The second said their original flights would go ahead as planned.
But in the second email, passengers were not given a link to automatically rebook onto their original flight, meaning they had to contact BA directly, the BBC reported.
The CAA has issued the below consumer rights advice:
(a) reimbursement within seven days of the full cost of the ticket at the price at which it was bought, for the part or parts of the journey not made, and for the part or parts already made if the flight is no longer serving any purpose in relation to the passenger’s original travel plan, together with, when relevant, – a return flight to the first point of departure, at the earliest opportunity;
(b) re-routing, under comparable transport conditions, to their final destination at the earliest opportunity;
(c) re-routing, under comparable transport conditions, to their final destination at a later date at the passenger’s convenience, subject to availability of seats.
CAA advice for consumers that were informed their flight was cancelled but the flight has been reinstated or is still running:
We understand that the airline is dealing with each case on an individual basis and encourage passengers to speak to them directly. Having been informed in error by BA that their flight was cancelled, those consumers that took action should not be left out of pocket, and any reasonable costs of re-booked flights should be claimed from the airline.