"We really need more people to see it before we get a sense of how it would play on Broadway," Working Title’s John Finn told the trade paper, while revealing that Stephen Sondheim saw and loved a preview.

Billy will have had a leisurely six weeks of previews by the time critics get to see it on May 11. Finn told Variety that during that time "we have been altering and refining the show quite substantially. [There has been] a quantum leap from the show we first opened." The number of previews was extended to allow the three boys alternating the title role to build up their stage stamina. New material has also been added throughout the process: the finale was incorporated on April 20.

Not only have the producers established a Billy Elliot academy in Leeds to groom young performers for the show, but they have also provided accommodation in Ealing. The residence houses around 20 children who appear in the show and, reports Variety, was recently moved from Shoreditch because the first property’s plumbing system couldn’t cope with that number of residents.

The show stars Liam Mower, James Lomas and George Maguire as the Billys. Stephen Daldry directs with a book by Lee Hall and songs by Elton John.

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