The Bank Holidays in May will still be limited by the pandemic restrictions, so moving them to after the restrictions are lifted, or creating additional Bank Holidays, will allow the UK population to make the most of these extended weekends.
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Long weekends in June and July after the Lockdown restrictions are lifted could allow more opportunities for retail and hospitality industries to recoup some revenue, as well as entertainment industries, for example music festivals. It will also allow for unrestricted private parties, and the perhaps prevent potential rule breaking in May for these covid-spreading events.