The theatre impresario, 74, did not attend the closing show at the Gillian Lynne Theatre in London’s West End on Sunday afternoon.
Instead, director Laurence Connor appeared on stage alongside the cast to deliver a message from the composer about the production’s premature end.
After the impresario received a backlash over the content of the letter, specifically where he made reference to a “costly mistake”, a spokeswoman for his company The Really Useful Group said the reference did not refer to the production itself.
She said: “The reference to a ‘costly mistake’ was never – and would never be – about the production.
“It related to the early opening of the show and the myriad challenges faced because of the Covid-19 pandemic, which the full text makes clear.
“As Andrew said in the letter, he is immensely proud of the show and that is hugely due to everyone involved.”
Last month Lloyd Webber announced Cinderella, which starred Carrie Hope Fletcher in the lead role, would be closing, less than a year after it premiered.
In the letter, read out to the audience at the Gillian Lynn Theatre, he said: “I am hugely sorry not to be able to be with you today.
“But I want to thank everyone, our fabulous cast, crew and musicians, the superb creative team, Laurence, JoAnn, Emerald, David and Bruno to mention just a few, and everyone who works in Really Useful and the Gillie for bringing Belleville brilliantly to life.
“I once wrote a song with the late great Jim Steinman called If Only.
“I keep thinking, if only we had opened three months later we wouldn’t have had to postpone our opening twice because of Covid. If only we hadn’t had to close for a month over Christmas and New Year, once again thanks to Covid.
“And if only we had had a crumb of help from the Recovery Fund, I promise you we would have been here for a very long while to come.
“Anyway, my huge thanks to everyone. We kept the government’s feet to the flame and lead the charge to get the West End open again.
“It might have been a costly mistake, but I am proud that we did and proud of everyone who supported me. Cinderella got some of the best reviews of my career.
“I am immensely proud of it and it’s hugely due to you.
“All my love, Andrew.”
The show’s premiere took place in August last year, having been scheduled for the previous month but delayed due to Covid isolation protocols.
The show opened with an audience capacity of 50% after Lloyd Webber rejected Prime Minister Boris Johnson’s offer for the show to be included in the coronavirus live events pilot scheme.
In December 2021, Cinderella was stopped due to “Covid-related absences”, alongside London productions of hit musicals Hamilton and The Lion King.
At the time, Lloyd Webber said it is “simply heartbreaking” to see the theatre industry “decimated” by cancellations, adding “no-one in the Government listens”.
He postponed Cinderella until 2022 “to avoid more disruption” as the number of Covid-19 cases increased across the country.
Written by The Crown star Emerald Fennell, Cinderella is described as a “complete reinvention” of the classic fairytale, and is based on an original idea by Fennell.