With thousands of UK holidaymakers having their flights home cancelled in recent days, many are worried if their extra costs will be reimbursed.

Families have reported forking out for food, accommodation and in some cases, alternative travel, due to the chaos. Rules exist for expenses to be claimed, but there appear to be some grey areas.

Figures suggest almost 2,000 flights to and from the UK have been cancelled due to a data glitch which hit the UK's air traffic control system. National Air Traffic Services (Nats), which controls most aircraft in UK airspace, said a rare system failure on Monday led to hundreds of flights being cancelled.

A family from London, spoke of how they are currently stranded in Turkey after their EasyJet flight from Antalya to Gatwick was cancelled on Monday. Samina Ahmed (in pic with family) is a school administrator and is missing out on work and a training course because of the delays.

The earliest flight home EasyJet initially offered the family was on 8 September - two days after her sons are due to return to school.

They were in Turkey for a family holiday but Samina, who is 17 weeks pregnant, feels "overwhelmed". She also says she has run out of medication she needs to take for her blood pressure.

She said that she was aware of another family who have rebooked a flight with a different company, but is worried she would not be reimbursed. "I just don't have that kind of money lying around," she said.

The Baker family are another among thousands of holidaymakers who have been affected. They were stranded in Palma, Majorca, when their EasyJet flight home to Brighton was cancelled on Monday.

They said that they were offered accommodation and a new flight in a week's time, but due to work and one of their daughters starting secondary school, they could not wait that long. Instead, the family embarked on an overnight ferry from the Spanish island to Toulon in France, where they are hoping to take three trains and another ferry to get back to Brighton by Thursday night.

Mr Baker said that he was unsure if they would be able to claim for the alternative travel. Excluding food costs, the family of four has forked out just under £1,000 so far on credit cards.

EasyJet has since offered Samina's family a flight back on 4 September, which she says is still too late. EasyJet apologised for the disruption in a statement and said that it was providing customers with assistance and hotel accommodation.

It added that it was advising anyone who has needed to make their own hotel or alternative travel arrangements that they will be reimbursed. It said due to it being a busy week for travel traditionally, its options for returning people to the UK were more limited on some routes so it was putting on five repatriation flights, as well as using larger aircraft with additional seats.

Rob Ward estimates that he is more than £2,000 out of pocket after his and his girlfriend's flight from Ibiza to London Heathrow on Monday was cancelled.

The airline suggested a Saturday flight back, but he found a return flight on Thursday with another airline that he paid for himself.

Rob, who manages two gyms, spent about £1,000 on hotels, £250 on new flights and says he will lose two days' income from his work as a personal trainer.

"We're stranded in Ibiza with little to no money and this has cost us an extra £2,100 and no flight for three days. You budget for a holiday, and this just can't be reasonably accepted with no help from the airline except 'keep your receipts'."

The chaos endured by thousands of UK travellers was a result of the company Nats receiving data that it could not process, leading to part of its system failing.

Nats controls most aircraft in UK airspace and receives millions of flight plans every year. Due to the failure, Nats reverted to a manual system - meaning fewer flights could be handled, causing a huge backlog.

The Civil Aviation Authority (CAA), the watchdog for the industry, says under UK law, people have legal rights on many flights to, from or within the UK. If a flight is cancelled, a passenger's airline must let them choose between either getting a refund or an alternative flight to their destination.

If another airline is flying to a person's destination significantly sooner, or there are other suitable modes of transport available, then people have a right to be booked onto that alternative transport instead.

Rory Boland, travel editor at consumer group Which?, said that expenses could be claimed by people who had booked alternative modes of transport as a result of there being no flights available.

"The airlines cannot claim an extraordinary circumstance forever," he said. In the cases of the Bakers and other families, Mr Boland said that nobody should be waiting a week for a replacement flight as the law stated airlines were required to offer alternatives at the earliest possibility.

"Waiting a week is never going to be the earliest opportunity," Mr Boland said. The joint interim chief executive of the CAA, Rob Bishton, also said that customers should keep every receipt if they have had to cover their own meal costs and accommodation and make sure that claims are not "excessive".

He went on to say that the organisation was working with airlines to avoid any incorrect information being given to customers. The CAA advises people to not spend more than is "reasonable" for costs incurred as a result of cancelled flights.

It also said that it expects airlines to respond to claims for reimbursement in a reasonable time. While people should be able to claim expenses, due to the disruption being not the fault of airlines, people are unlikely to be eligible for extra compensation.