With Warner rolling out their DC Extended Universe from next year, the superhero film market is going to become a crowded place, as rival studios fight for key release slots. Warner’s much-anticipated Batman v Superman: Dawn of Justice has already shifted release dates twice, first from July 2015 to May 2016, and then forward to March 25 of next year, to avoid a clash with Marvel’s Captain America: Civil War.

Now, Warner CEO Kevin Tsujihara has spoken to The Hollywood Reporter about the decision to move the film to its current date, and how it contributed to a disappointing summer gross for the studio this year. “It was a tough decision at the time because it was going to create a hole in 2015,” he said. “But it was absolutely the right decision for the franchise, for DC and the movie.

“Having seen the movie multiple times, and again last night, I’m extremely confident it was the right decision to make the movie better. And it’s so important for the studio to get the foundation right on DC.”

Batman v Superman will be the second film in the Extended Universe, following 2014’s Man of Steel. Warner have announced an ambitious release slate over the next few years, including David Ayer’s Suicide Squad–due next August–and future titles such as Wonder Woman, Aquaman, The Flash, more Batmans, and two Justice League movies.

Batman v Superman: Dawn of Justice is directed by Zack Snyder, and will showcase Ben Affleck’s debut as the Caped Crusader. Henry Cavill returns as Superman, while Jesse Eisenberg and Gal Gadot take on the roles of Lex Luthor and Wonder Woman respectively.