During their panel at SDCC, WB showed a concept reel of Green Lantern and revealed the titles name is changing to Green Lantern Corps. Originally it was simply titled Green Lantern and many people assumed it was a reboot to the series, but that is also changed. WB announced it will be a follow up to the original movie starring Ryan Reynolds.
From there details get a little more scarce as there is no confirmed cast or characters just yet (though this would coincide with earlier rumors about it featuring Hal Jordan AND Jon Stewart together). They did showcase an image of several Green Lantern’s including some Earth bound ones that would include long requested Jon Stewart alongside Hal Jordan. Also worth noting is a quote from Ryan Reynolds noting he is sticking with Deadpool and has no plans to return to any other superhero movies, so he may be replaced as well.
Green Lantern corps obviously references several Lanterns teaming up, and since it is a follow up to the previous film that could mean a return for Sinestro as well.
The film is keeping the June 19, 2020 release date.