Since the working title "Supernova" first cropped up in January, it's been widely assumed Fox's next X-Men film will revisit the seminal Marvel Comics storyline "The Dark Phoenix Saga," and franchise producer Simon Kinberg has done little to discourage that notion. However, it turns out, perhaps unsurprisingly, that the film isn't actually called "X-Men: Supernova" -- but it's looking more and more to be a Dark Phoenix story.

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While promoting "Logan," Kinberg explained to Slash Film that "Supernova" was merely a code name, which producers have since abandoned in favor of a new one.

"One of the things we do when we make these X-Men movies, to be totally candid, is — any of these movies, it’s on 'Star Wars,' too — is you come up with fake names to throw people off the scent," he said, "and when you’re out making the movie, the signs that show you where the locations are say 'Nova,' or whatever the fake title is, and people figure it out, and I don’t even know why we do it anymore."

Kinberg, who has insisted it's "premature" to say he'll direct the film, declined to directly address rumors of a Dark Phoenix storyline, and instead circled back around to the mistakes of 2006's "X-Men: The Last Stand," which used Jean Grey's arc as a subplot.

"Well, I can’t comment on what we’re doing with this next 'X-Men' movie," he said, "but I think a way to talk about it potentially, is to talk about 'X-Men: The Last Stand,' and then that being a Dark Phoenix movie that we didn’t get quite right. I think of maybe a few mistakes we made in that movie — and every movie has mistakes — but the main mistake we made in that movie was taking the Dark Phoenix story, which is such a vast and profound saga, and making it the subplot of the movie as opposed to the main plot of the movie. I think if we were to make a Dark Phoenix movie in the future, it would be a Dark Phoenix movie about her struggle, and really should be the A plot and the primary of the movie."

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So, yeah, you'd probably be safe to go with "Dark Phoenix Saga" is your very nerdy office betting pool.

But if you require additional evidence, "Game of Thrones" star Sophie Turner confirmed last month that she'll reprise her "X-Men: Apocalypse" role as Jean Grey in the film.

Kinberg added that he and fellow producer Hutch Parker have discussed that the film's story -- whatever it may be about --  "would be something bold and radical and expand the universe in the same way that 'Logan' feels bold and radical and certainly 'Deadpool' does as well."

The film is expected to begin production in May in Montreal.