The Marvel Cinematic Universe, or rather the people working on it, have no set rules about time travel and the multiverse, another bit of proof that they no longer care about putting out a shared universe or even a competent product. With the upcoming release of a third Ant-Man movie, this one delving further into the multiverse, John F. Trent at Bounding Into Comics goes over all the contradictory statements about time travel and the nature of the multiverse between the movies and shows.
Here’s another compared to the comics: in a trailer or clip or wherever I saw it for Doctor Strange In The Multiverse Of Madness, someone refers to the main MCU as 616, a joke based on DC calling their primary universe Earth-1 when they have a multiverse. That’s an intended nod to the comics…except that’s the comic universe. The whole point of Marvel’s numbering system is that each continuity, each show and comic and video game and movie (and probably other media formats as well) are in their own universe and thus have their own designation in the multiverse. According to the Marvel Database, the MCU is listed as Earth-199999 according to volume 5 of Official Handbook Of The Marvel Universe A to Z. So in other words, the people behind the MCU right now have absolutely no idea what they’re doing when it comes to time travel and the multiverse, and now they’re doing even more stories with that theme and introducing their version of Kang. I see this ending poorly.