From an AP article about
Star Trek Beyond, and what to do about making the fourth movie without Anton Yelchin:
The series will live on, of course. On Monday Paramount Pictures announced that there will be a fourth film, which will see the return of Kirk's deceased father (Chris Hemsworth). As for Chekov, Abrams said they've started thinking about how to deal with his absence in the continuing story, but that it's also "too early to talk about."
"There is no recasting," Abrams said. "I know he literally was a re-cast of a prior thing, but ... we have some other thoughts."
"No recasting" would mean carrying on without the character of Pavel Chekov. In which case, I have one word for them to consider: Saavik. She occupied the navigator's chair in
The Wrath of Khan, in Chekov's absence from the
Enterprise, so she'd be the obvious choice.
And it'd allow them to add a sidebar plot about Uhura's being jealous, out of fear of losing Spock to one of the few remaining members of his own race. (I haven't yet seen the 2nd film, so I'm guessing, at this point, that they're still an item.)