Well, according to friend buying seats, they are announcing Munoz for B'way, July on. My guess is: he'll pick up 7 of the 8 performances a week on B'way, and stay a while. He wouldn't sell tickets in Chicago, and perhaps they'd like a company that rehearses together from the day one. Many cast members have vocally embraced that part of the HAMILTON experience: building the show incrementally as a company. I'd bet Javier stays put.
A delicate subject, but not really: eventually, Miranda will need to move on. And be done with the role. He will want to. And the show will mostly feature other Hamiltons. Most people will see other people in the role. It's just a fact. So it will be thrilling to consider the wonderful array of talent waiting in the wings, to quote the opening number.
"I'm a comedian, but in my spare time, things bother me." Garry Shandling