Warner recently changed the release windows for some major DC movies, including Aquaman and the Lost Kingdom and The Flash, which were both delayed to 2023. Fortunately, Batgirl wasn't mentioned, and it seems like we could expect it later this year as planned.
Leslie Grace, who plays Batgirl, confirmed the filming wrap on Instagram during the weekend saying "THANK YOU to every person on this crew who made it all happen". The most hype surrounding Batgirl comes from the fact that Michael Keaton will be back as Batman in it, but the premise of the movie itself seems promising.
The girl under the mask is Barbara Gordon, who is Commissioner Gordon's (the guy with the Bat Signal, played by J.K. Simmons) daughter. It seems like we can expect a pretty grim story, as Leslie Grace previously said to Elle Magazine:
"I can't say much about what she is going to do, but Batgirl becomes her own hero. [Her origin story] is crazy dark, like a lot of other superheroes, but I like that she becomes Batgirl because she wants to make a difference in the world. She feels like people underestimate her as Barbara Gordon, and I relate to that."
Batgirl's nemesis in the movie is Firefly, played by Brendan Fraser. It has a script written by Christina Hodson (Birds of Prey, The Flash) with Adil El Arbi and Bilall Fallah directing.