Actually scheduling conflict wasn't the reason given - there was no reason given and no press release issued - there was simply a post on the twitter feed and Facebook site which said: "Welcome @suttonlenore to the fabulous cast of #AnythingGoes. We can't wait to sail away with you this summer at the @Barbicancentre" - and some new artwork with Sutton Foster on it.
However a story in the Daily Mail it was reported that Mullally had said in a statement yesterday that she's 'heartbroken to miss the opportunity to work on this amazing classic musical. My body has informed me (mainly while at tap class) that I need to have a few rods replaced before I can get back on stage, hopefully that will be as soon as possible.'
Though what that actually means is anyone's guess!