Heathrow said it has posted extra staff at the terminals and warned BA passengers on flights before 6pm not to go to the airport.
Footage filmed at Terminal 5 showed long queues at customer services, after passengers had been advised that they would be unable to rebook due to systems remaining down
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It's the biggest event of the year in Brighton - but it's feared a bin strike at this year's Pride Festival could leave the city in a mess.
Holly Green has the pollen forecast for the ITV Meridian region.
Holly Green has the overnight forecast for the ITV Meridian region.