British Airways has admitted it made a mistake when it advised passengers flights were cancelled, and told them to book new ones.
Passengers have described “confusion” as cancelled flights were reinstated, but only after some of them rebooked.
BA apologised for any concern caused and said the email was an “error”.
“We are getting in touch with all those customers this afternoon to clarify that their flight will go ahead as planned,” a spokesman said.
“We are sorry for any confusion and inconvenience this has caused.”
He encouraged anyone who had spent money on new flights to get in touch. “We will deal with each case on an individual basis,” he added.
The airline announced that pilots would strike on 9, 10 and 27 September.
But on Saturday it told some passengers with flights between the 8th and 12th that their flights had been cancelled, and they should rebook or seek a refund.
Josh Sullivan, 27, from Trowbridge, had been due to fly with BA back to London on 8 September from his stag do in Prague.
He said his best man, who organised the flights, bought another pair of flights from RyanAir for £180 when he was emailed to say the flight had been cancelled.
BA has now informed him the flight has not been cancelled.
“The fact that they’ve un-cancelled it, we went through all this aggro today for no reason – and now I have two flights back from Prague and we’re £180 out of pocket,” Mr Sullivan said.
“It’s a complete mess,” he added.
BA explained there could still be some disruption to flights on 8, 11, and 12 September.
“Airlines have a very complex operation and during times of widespread disruption, there can be knock-on effect onto flights on other days,” BA said.
It added: “We are doing absolutely everything we can to prevent this unfair action from taking place and ruining our customers’ travel plans.”
BA says it carries 145,000 customers every day – with a fleet of more than 280 aircraft – and a BA plane takes off from somewhere in the world every 90 seconds.
Passengers described “utter confusion” on social media on Saturday.
Some said they had made alternative travel arrangements after being unable to get through to BA’s customer services.
A spokesman for BA said he did not expect the airline to release details on how many people had been affected by the erroneous email.