DCEU: 12 Things We Learned From 4Chan's Latest DC Movies "Leak"
6. Dark Universe Could Take Aquaman's Original Release Date
The Rumour
Either Suicide Squad 2 or Dark Universe will most likely be released on Aquaman's previous release date of October 2018.
Response
Though neither of the ensemble movies are even filming yet (making a release in just over 18 months seem improbable), it's not out of the realms of possibility that they'll be expedited to the screen in that time.
The Justice League Dark project has been in some state of production for a long time, and Suicide Squad 2 is assured with the financial success of its predecessor. Of the two, releasing the more supernaturally-focused property (Dark Universe) in the same month as Halloween would definitely be the smartest move.
Even more likely is the possibility of Gotham City Sirens coming in 2018, since it feels like it's far more on the production trail already.