Producers have announced that the West End production of Waitress, which opened at the Adelphi Theatre last year, has closed.In a statement posted on social media, producers said: 'It is with great sadness that we announce the closing of our beloved London production of Waitress the Musical. As you'll be aware, we've had to temporarily lower the curtain at the Adelphi Theatre and it's now unlikely that the diner will reopen once this period of uncertainty is over.'If things do change and there...