Marvel Studios has quite literally revolutionized the way movies are made. They were the first to fully realize a cinematic universe, something that every other studio in Hollywood is now chasing, and they also set up their entire interconnected slate as “phases”. This wasn’t all an entirely new notion—Marvel was basically just copying how comics have been telling stories for years—but it brought a refreshing spark to the blockbuster landscape, and fans began anticipating the beginning and end of each new phase.

Phase 1 was the first Marvel movies that lead up to the make-or-break one, The Avengers. That team-up movie served as the conclusion to Phase 1, while Iron Man 3 kicked off Phase 2. Then Phase 2 concluded with Ant-Man, leading into Captain America: Civil War as the beginning of Phase 3. But it’s now been nearly a decade since Marvel began this journey with the first Iron Man, and it sounds like yet another evolution is in store.

Collider’s own Steve Weintraub recently spoke with Marvel Studios president Kevin Feige in anticipation of the release of Guardians of the Galaxy Vol. 2, and in speaking about the prospect of actors’ contracts running out and potentially killing off major characters in Avengers: Infinity War and the untitled Avengers 4—which have been described as the culmination of the entire MCU thus far—Feige teased some serious uncertainty with regards to the MCU’s future:

“We’ve been lucky that [contract expirations] haven’t factored in too much. We’ve had people under contract for certain films, then we’ve had new ideas and new directions like Civil War like we wanted to do, and we’ve been lucky enough to make new contracts. Or Spider-Man: Homecoming, the cast has been awesome in their enthusiasm for the direction and the storylines that we’ve been telling. So it really does, right now, all start with where we wanna take the stories. Certainly as we get to Infinity War there is a sense of a climax if not a conclusion to, by the time we’re at untitled Avengers 4, the 22 movies that will have encompassed the first three phases of the MCU. And what happens after that will be very different. I don’t know if it’s Phase 4, it might be a new thing.”

This is the first we’ve heard that the notion of “Phases” might end after Avengers 4, or at least the notion that life after Avengers 4 might not exactly be “Phase 4.” Whether that means a radical reboot of the MCU, focusing on new characters as folks like Robert Downey Jr., Chris Evans, and Chris Hemsworth depart, is unknown. But Feige did note that not a ton of focus is going into what’s happening after Avengers 4 right now, as Marvel Studios has its hands full with eight ongoing productions at the moment: