LONDON—Sparkling wine, confetti, a midnight countdown: It’s not New Year’s Eve, but it might as well be for England’s clubbers. After 17 months of empty dance floors, the country’s nightclubs are reopening with a bang. From London to Liverpool, thousands of young people plan to dance the night away at “Freedom Day” parties the moment it becomes Monday, which is when almost all coronavirus restrictions in England are due to be scrapped. Masks will no longer be legally required, and with social distancing rules shelved, there will be no more limits on people attending theatre performances or big events. Nightclubs, which have been shuttered since March 2020, can finally reopen with no occupancy restrictions or mask and testing requirements. Many of the reopening parties planned for the occasion sold out days ahead. It’s “the moment we’ve been waiting for, that our customers have been waiting for,” said Tristan Moffat, operations …