It's going to take awhile before you finally get to see The Flash on the big screen in his own standalone film, which is kind of ironic if you think about it.
According to Variety, Warner Bros. has delayed the start of filming for the yet-to-be-titled film, which was originally expected to begin shooting in March 2019 (even though it's yet to be formally greenlit). Variety adds that the script for the movie is still in the stage of being tweaked, while the studio doesn't believe that said tweaking will be done in time to begin filming five months down the road.
While that's already a setback, the timing for that will be made worse by the fact that the man who will be portraying the hero, Ezra Miller, has a role in the third film in the Harry Potter spin-off Fantastic Beasts series, which is set to begin filming in July. Due to this scheduling conflict, The Flash is on track to delay production until the end of 2019 which will likely mean it's headed for a 2021 release date.
As previously reported, the movie saw its pulse revived in January 2018 when it was announced that Spider Man: Homecoming writers John Francis Daley and Jonathan Goldstein would serve as the movie's directors. The duo's hiring filled a year-plus vacancy, which was created after director Rick Famuyiwa left the film in 2016 over creative differences.
As for what DC has coming up that is more, uh, finished, that would be an Aquaman movie for this upcoming December, a 2019 Wonder Woman sequel, a Suicide Squad follow-up, and a Joker movie with Joaquin Phoenix serving as the lead.