Assuming next month's Justice League movie is a success, more DCEU movies are a given, which will include Justice League sequels.
Speaking with Total Film Magazine, J.K. Simmons confirms more Justice League movies are currently in development ahead of the November release of the first film.
Total Film questions J.K. Simmons about being seriously pumped up (see the image below) and what can we expect from his Commissioner Gordon in Justice League, which sees J.K. Simmons confirm a script for Justice League 2 is being worked on:
"Well, Commissioner Gordon wears a trench coat in every scene, so I don't know that the 'pumped up' part is going to be all that evident, especially when you're standing next to Batman! But this is the first Justice League movie - we hope - of a few. They're working on scripts for The Batman and for the next Justice League movie. It introduces my incarnation of Commissioner Gordon. I don't have a lot to do. I feel like I just dipped my toe in the water of who Commissioner Gordon will be."
JK Simmons is also asked about getting to switch on the Bat Signal:
That's an iconic thing, and obviously there are some very big shoes that I'm attempting to step into. Some really, really wonderful actors have played that part before. It's like all of a sudden everyone in London is doing Hamlet. Now it's my turn to be Gordon.
Justice League has a November 17, 2017 release directed by Zack Snyder, with the story by Chris Terrio and Zack Snyder, the screenplay by Chris Terrio and Joss Whedon, and stars Ben Affleck as Batman, Henry Cavill as Superman, Gal Gadot as Wonder Woman, Jason Momoa as Aquaman, Ezra Miller as The Flash, Ray Fisher as Cyborg, J.K. Simmons as Commissioner Gordon and Willem Dafoe an Atlantean, Nuidis Vulko.
Fueled by his restored faith in humanity and inspired by Superman’s selfless act, Bruce Wayne enlists the help of his newfound ally, Diana Prince, to face an even greater enemy. Together, Batman and Wonder Woman work quickly to find and recruit a team of metahumans to stand against this newly awakened threat. But despite the formation of this unprecedented league of heroes—Batman, Wonder Woman, Aquaman, Cyborg and The Flash—it may already be too late to save the planet from an assault of catastrophic proportions.