David Ayer says Suicide Squad originally had more connections to Justice League, but fans shouldn't get carried away with assumptions just yet. Suicide Squad is notorious for its behind the scenes issues, with a significant portion of the movie being reshot at the last minute to fit it into a lighter, more comedic tone full of pop music cues. The theatrical version of the movie already included a mid-credits scene connecting it to Justice League, but what Ayer is referring to would have been even more, but probably not quite what fans are thinking.
The Suicide Squad director recently responded to a fan who tweeted concept art for Suicide Squad that seemed to have a lot of connections to Justice League. In his tweet, Ayer said "This is right. Enchantress was under the control of a mother box and Steppenwolfe was prepping an invasion with a boom tube. Had to lose that then the JL story arcs evolved." He also tweeted the minions were originally parademons and the final fight was supposed to be with Steppenwolf. Ayer has a history of trolling fans with fake Suicide Squad plot-points, recently suggesting Joker had a fight with Superman, but there may be a kernel of truth to this. Ayer just isn't clarifying the full story.
While this may seem like par for the course with Warner Bros. treatment of these movies, cutting down Batman v Superman: Dawn of Justice for theaters, totally changing Suicide Squad at the last second, and giving Justice League intensive reshoots to drastically alter the story and change the tone. This change, if true, would have had nothing to do with that, though. It would have happened far earlier in production and isn't related to any of Suicide Squad's already highly publicized reshoots.
It's important to keep production timelines in mind. David Ayer signed on to write and direct Suicide Squad in September 2014. Shortly after, he said the movie would be "Dirty Dozen with Superheroes." Batman v. Superman: Dawn of Justice was in post-production at the time. Suicide Squad began principal photography in April 2015, ending in August 2015, and Chris Terrio finished Justice League's script during this time. Set photos from principal photography revealed the version of Enchantress' minions that were in the final movie, characters Ayer said were originally supposed to be parademons. This proves the changes to distance from Justice League happened long before Batman v Superman's negative reaction, Suicide Squad's reshoots, and Justice League's rewrites.
Based on the timeline, the changes to Justice League Ayer is referring to would have been changes made by Terrio and Zack Snyder, not by the more notorious WB executive requested changes everyone's familiar with. In fact, Ayer's original cut was test screened shortly after the release of Batman v Superman: Dawn of Justice and there were no traces of Steppenwolf or parademons even before reshoots. These elements were all surely abandoned in pre-production.
These kinds of changes are more than common in pre-production. Batman v Superman: Dawn of Justice was once supposed to feature Metallo, Suicide Squad also has concept art with The Scarecrow as a villain. These are all interesting details of the movie's development, but it's a totally different narrative from Suicide Squad's other changes during reshoots.
While it's always fun to see connections between movies in a franchise like this, these changes were actually a step in the right direction. The Suicide Squad isn't the right place to set up Apokolips and Mother Boxes, and the problems with that movie were due to the reshoots, not the pre-production rewrites.