According to this document, it is mandated that Airlines allow cancellation with a FULL REFUND and applies to ALL reservations made SEVEN DAYS or MORE PRIORDiscover Expedia' Comprehensive Cancellation Policy 24-Hour Free Cancellation: If you need to cancel your flight within 24 hours of booking, Expedia allows you to do so for free If you are able to cancel your flight, you are responsible for paying Expedia's flight cancellation fee of £25 per passenger on top of any cancellation fees
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