Hopefully never. But as others have said, it comes down to whether she wants to lease the rights--and I'm betting that's a no. When she gets to Tina Turner's age, it will be a yes, and probably as a similar vehicle for herself, too.
I'd add this to the list with her memoirs or a film about her early days.
About the former, she says she wants to but isn't ever going to sit down and spend years talking about the past, because she's always more interested in new projects.
As for the latter (resembling what others have said here about a jukebox musical), she's always said no or even stopped other films from happening because she says she wants to tell it. See: memoir.
She did write a musical in 2003-4 called HELLO, SUCKERS about vaudeville star Texas Guinan (yes, the CHICAGO Act 2 opening line is inspired by her famous call to the audience). But she opted to do her CONFESSIONS album instead. Good career move.
So, I've always assumed she'd be an artist who'd rather write a new show as opposed to a jukebox one. Thing is, many have tried and if you want a successful one, you need a very strong collaborator like a Harvey Fierstein.
Back in 2014 I wrote and directed a jukebox musical with Madonna's songs (translated to catalan) in Barcelona. It was only an amateur production, but if anyone is interested just write me.
It doesn't follow her life, though, it's a completely new story, more in the line of Mamma Mia than Jersey Boys or The Cher Show...
M’s instagram has been full of her collaborating on something with screenwriter Diabo Cody, who also happened to recently write the book for Jagged Little Pill.
I will say it one more time, does every possible rock/pop star really need their own Broadway musical? Please stop it and try being creative and write an original story and music.
I find it interesting that she's working with Diablo Cody on a screenplay about her life when for a few years now there's been a floating screenplay called Blonde Ambition that was like on top of the Blacklist of unproduced screenplays that she doesn't approve of. It seems Madonna sees an opportunity to take control and tell her own story before someone else does in a "major" film production and I guess quarantine has given her downtime to do such a thing.
I guess I'll be the lone voice of dissent and say I'd prefer a jukebox musical with a plot vs a biomusical. Madonna's catalog is interesting enough (at least compared to other pop acts) that a good writer could craft a story using her songs. What's the legality on unauthorized productions? For example, did the Cruel Intentions musical get the rights to all those songs or were they cleared under parody?
I think it's a genius idea. If the script is good, it's a project she was born to direct. But a good script for a biopic is always challenging, so sadly, that's a big "if".
One thing I don't get is the pearl-clutchers over her directing. People write their memoirs. Male movie directors make movies about their childhood all the time, every year. This is no different than either, except if one takes issue with a female artist telling the story of her success; as in, she can live it once, but she's not allowed to re-live it because now someone must tell it with negative traits included.
As for a musical, I still think we're a ways off from that and she'd rather write a new one. But if the film is successful, who knows?
Another thought I had was that maybe Madonna won't even consider having a full-blown musical with her catalogue until she feels she's done making music, and that probably won't happen until she dies. It's one thing to let a friend use her catalogue for one special episode of Glee, and of course she has no control over the songs she does not own, but for an actual authorized musical, which will probably be a bio-musical, she probably feels it can't really be done until she's finished. I think this movie is being done thanks to that screenplay, Blonde Ambition, that Universal purchased. Maybe once Madonna publicly denounced that project, Amy Pascal of Universal contacted Madonna about doing her own movie instead of producing Blonde Ambition, and here we are now.
For what it's worth, I was skimming the subject lines on the front page of the message board and did a double take because I thought this thread's subject was "How long until a Jason Momoa musical".
And I thought to my own surprise "Well, you know what, I'd probably see that."