Customers with a cancelled flight have two main options under the law to get them to their destination.
Consumer expert and host of The Home Show Sinead Ryan was speaking as all eight of France's major unions have called a ‘General Strike’ for Friday.
One Lunchtime Live caller, Kate, got stranded in Nice during an Air Traffic Control strike in France last month.
"The interaction with Aer Lingus afterwards was a bit of a disaster to say the least," Kate said.
"At that stage we'd gone pass the three hour delay mark, so I figured in my head we're due for the European compensation.
"We get a text to say ground staff can't get accommodation - go figure - and keep the receipts yourselves and send them on to us.
"Myself and my two other colleagues just said, 'We need to sort this out and get a hotel'.
"We literally picked the cheapest thing we could get and we needed to find by plane, automobile - anyway - just to get back home.
"We did manage to find a flight from Lyon, but we needed to get to Lyon.
"We hired a car, a basic model, just to get us there.
"We got all our receipts and sent in the claim."
Kate said they just want to get reimbursed for the cancelled flight.
'One of two options'
Sinead said the law around flight compensation is quite clear.
"A flight cancellation, anything with very little notice, the airline regulation says under seven days... you must be offered one of two options," she said.
"One is to take a full refund; if you take that option, you're kind of on your own then to get yourself home.
"The second option is to be re-routed at the next available opportunity.
"The airline will always try to use themselves as the first re-route [option].
"When they say, 'There's no flight until Friday', what they mean is with Aer Lingus.
"If they can't find a flight with their own airline, they're obliged to go and look at other airlines."
Sinead said the option to be re-routed is generally the better one.
"I would say, as a general rule, it's always better to go for the re-route option than the refund option," she said.
"You won't necessarily get where you need to be quickly and that's part of the problem.
"The way it's supposed to work is they find you a hotel, they give you your meals, they say 'Here's what we're doing in the next 24 hours while we fix it'.
"In a lot of times, if everybody's grounded, they simply cannot do that.
"What the law says - EU 261 - where the airline doesn't do that, fails to do it or can't do it, then you make your own arrangements and reasonable expenses... they will reimburse you for you having to have made your own way home."
Sinead said there is also a system for people who are unhappy about the reimbursements offered.
"You can complain to the Aviation Regulator and put through a claim to try and get more," she said.
"You have to apply to the regulator in the country in which you are stranded.
"So, it's not Aer Lingus and it's not Ireland - in your case it's going to be the French Aviation Regulator," she added.