AMSTERDAM (Reuters) - Eurovision Song Contest organisers on Monday announced dates for the 2021 event in Rotterdam with the same “Open Up” theme planned for this year’s edition before it was cancelled due to the coronavirus pandemic. Semi-finals will be held on May 18 and 20, and the final on May 22 -- with 41 countries participating despite significant doubts about the exact format as COVID-19 continues to cause restrictions around the world. The European Broadcasting Union said it was working with four scenarios ranging from a relatively normal version of the contest to one in which the Netherlands is in lockdown. In that case, performances would take place without live audiences. Organisers said they believe live performances with reduced audiences and social distancing measures should be possible at the Ahoy Arena in Rotterdam.