Director Seth Grahame-Smith has left The Flash. The official explanation: "creative differences."
Sources at WB tell me that this is just one part of what's going on behind the scenes at the DC movieverse. Zack Snyder and Geoff Johns were taken aback at critical and audience reaction to Batman v Superman, I'm told, and WB execs have found themselves at odds with Snyder over his vision for Justice League and the DC movieverse going forward. Of course Justice League was scheduled to start shooting mere days after BvS was released, which meant WB couldn't take any definitive action - like removing Snyder or delaying the movie to make changes - without poisoning the box office for BvS. The result? Lots of fights between Snyder and the WB execs, and lots of pressure from Burbank on Snyder, who is shooting in London.
I'm not sure what the exact nature of the creative differences on The Flash are, but I'm being told that this may not be the only movie impacted by the aftermath of BvS. According to multiple, reliable sources James Wan is feeling a tremendous amount of trepidation about Aquaman. It's important to remember two things - Fast 7 was a very difficult process for him, even without Paul Walker's tragic death, and James Wan doesn't really need Aquaman. With The Conjuring 2 and Lights Out (which he produced), Wan will be owning WB's summer slate, bringing in a lot of money with movies that cost a fraction of Aquaman. Aquaman needs Wan, and right now Wan is trying to decide if he needs that hassle.
It will be interesting to see how things shake out. Wan has the upper hand on Aquaman, so maybe he'll be able to make that work in his favor. I keep hearing that it could be delayed in an attempt to get the film right, but who knows. Justice League is going to be Justice League, no matter how hard the studio rides Snyder. As for the rest of the slate - Suicide Squad, the weird side movie, looks like it's the hail mary pass for the DC Movieverse, at least until guaranteed winner The Batman gets here.