Non-Cook trips booked at one of Cook’s high street stores may still be valid according to the CAA, which has urged customers to check their bookings “with their nearest Abta-approved travel agent” before making any alternative arrangements.

“We would like to make it clear that some holidays booked through Thomas Cook travel agents remain valid,” said CAA chief executive Richard Moriarty in the authority’s latest update on its Cook repatriation mission, Operation Matterhorn.

Addressing consumers, Moriarty added: “This is because they are booked with another tour operator outside of Thomas Cook Group. Check your booking documents and, if you still aren’t sure if your holiday is valid, confirm with your nearest Abta approved travel agent.”

Following Cook’s collapse on 23 September, leaving more than 150,000 Cook passengers stranded overseas, the CAA launched the UK’s largest peacetime repatriation effort – Operation Matterhorn – which has so far flown home around 132,000 people.

The CAA now predicts Matterhorn will extend to around 800 rescue flights in total, down from around 1,000, after it began combining more scheduled Cook flights into single repatriation flights.

Some 94% of those repatriated so far have been brought home on the same day their cancelled Cook flight was due to depart.

The final 15,000 to 20,000 outstanding Cook passengers are due to be brought home over Friday, Saturday and Sunday, with Matterhorn scheduled to wrap up on Sunday (6 October) before the CAA on Monday embarks on what will be the largest refund programme in the history of the Atol scheme.

Cook collapsed with around 360,000 forward bookings, and refunds under Atol are estimated to amount to in excess of £400 million. A claim form will be made available via thomascook.caa.co.uk on Monday morning (7 October).