Airline algorithms have pushed prices up. | Miquel À. Cañellas

Over the past 48 hours, there has been increased demand for flights back to the UK among British holidaymakers who have not been vaccinated twice. And because of an increase in demand, airlines' pricing algorithms have reacted accordingly. One report on Friday pointed to the price of tickets for Sunday having risen by four times. The deadline is 4am on Monday.

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Meanwhile, and despite the exemptions for double-vaccinated travellers and under-18s, there is growing concern at the slump in bookings for Mallorca and at the possibility of the islands being further reclassified - this time red. It isn't only Mallorca and the Balearics that are being affected; the likes of Benidorm are as well. The falloff in demand is especially evident among younger people who have not been vaccinated.