Date: 19th February 2019
After claiming none of the original characters from 2016's Suicide Squad would be returning in James Gunn's upcoming reboot for DC, the story has changed. And now it's sounding very likely that Margot Robbie will reprise her role as Harley Quinn in this quasi-sequel simply titled The Suicide Squad.
Forbes has offered an update on their previous report: "I have learned from sources close to production that in fact, the information about Harley Quinn being absent from the new Suicide Squad movie is no longer up to date -- she is indeed expected to appear in James Gunn's The Suicide Squad, which is expected to begin production later this year."
James Gunn was originally brought onto write The Suicide Squad after being fired from Guardians of the Galaxy Vol. 3 by Disney. Now, he's in talks and pretty much locked in to direct the movie. When news broke that he'd decided to take the helm, it was widely reported that the filmmaker is working with a new set of characters in what will be a complete revamp of the entire series.
Source: Press Release