In terms of troubled DC productions, The Flash might be at the top of the list. They have gone through three directors and more writers than we can name here. Somethings keeps getting in the way of getting the production off of the ground. It was rumored to have a May 2020 start date on the production, but that clearly didn't happen. The movie has gone from having a 2018 release date to finally settling into November 4, 2022 release date. We got some concept art back at DC FanDome, and we have had some casting announcements. Both Michael Keaton and Ben Affleck have been confirmed to play various versions of Bruce Wayne, aka Batman. There are also rumors that Ray Fisher was eyeing a role in the movie; Cyborg is name-checked when Miller appeared in the CW's Crisis on Infinite Earths, but considering how contentious things are between Fisher and DC these days, that probably won't happen. Billy Crudup is also rumored to return as Henry Allen, reprising his role from Justice League.
The latest director set to helm this movie is Andy Muschietti, while Christina Hodson was also brought on to work on the script for The Flash, which has more or less been confirmed to be some version of the Flashpoint storyline. Now it sounds like we might know when things are supposed to get off of the ground. According to Backstage (via ComicBook.com), The Flash is looking to start production in the United Kingdom in April 2021.
The Flash will shoot at Warner Bros' Leavesden Studios, and this all lines up timeline-wise. This will be an effects-heavy movie, so giving themselves a year and a half to shoot and get post-production done is probably the right idea. Also, The Flash is the perfect movie to do a lot of short cameos from the TV universe to others, and a longer period for post-production could mean setting up more of those cameos. We still have a couple of months to go, and things could very much change between now and then. Hopefully, nothing else happens to set this movie back again. Maybe everyone will be able to keep their star from allegedly choking female fans.