Director of the last two Planet of the Apes movies, Matt Reeves, was hired a while back to write and direct the next solo Batman adventure, but he made it clear that he would need time to "crack the story." Well, if the man himself is to be believed, the story must have been cracked because he's begun writing the script.
While appearing on The Q&A Podcast to talk about War for the Planet of the Apes, Reeves said that he had finally "worked out the story" and begun the process of actually writing the script. That's not news, necessarily, other than to say that rumors of the DCEU's demise have been greatly exaggerated.
I think that the plan, at this point anyway, is to give him some leeway to do whatever he wants without being constricted by the already established universe, and they can just piecemeal get rid of what they want to get rid of over time. Yes, there will always be a small but loyal fan base who will always wish that Zack Snyder could make just one more movie to make it all come together, but I think the rest of us have moved on.
I could personally care less if he keeps Affleck or gets rid of him. All I care is that it's a good story, worth telling. Reeves delivered as much with his two Apes films. I trust he'll do it again with Batman.