Word of this development comes from the El Fanboy Podcast at the website RevengeOfTheFans.com. Editor in chief Mario-Francisco Robles says that he learned this from a source at Warner Bros., but stressed that it was only a rumor and could thus turn out to be incorrect.
Nevertheless, this fits other rumors that have popped up lately, implying that Warner Bros. wants to fast-track this particular movie. In particular Henry Cavill, who plays Clark Kent/Superman in the DCEU, has said that he would like to jump back into the role sooner rather than later.
The original Man of Steel, which came out in 2013, was the first entry into the DCEU. It proved quite profitable and convinced Warner Bros. to continue with its shared universe idea, though audiences were divided on its darker, deconstructive take on the Superman mythos. The next entry, Batman v Superman: Dawn of Justice, is generally seen as having even more problems, and the DCEU has been trying to course-correct ever since.
The franchise’s most recent entry, Justice League, tried to temper the darker aspects by director Zack Snyder with the more mainstream and quippy work of Joss Whedon. While the final product came off a bit schizophrenic, many did like the soft retcon it made to Cavill’s Superman, giving him a much more friendly, traditional portrayal. As such, many believe that a new Man of Steel movie would be a good way to help cement the more optimistic tone of the DCEU.