Jon Favreau announced he is he’s already written the fourth season of the series. In his word -  "I’ve written it already. We have to know where we’re going, to tell a fully formed story, so we mapped it out Dave and I  and slowly you write each episode." He was writing during post production (Of Season 3) because all of it needs to feel like a continuation and one full story.

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Filming of season 4 should begin this, October at Manhattan Beach Studios, California. Also  some additional information, there will be  new armour for Moff Gideon, his stormtroopers and a new jetpack for Din.

Also looks like  a second season of The Book of Boba Fett is coming and possible Ahsoka season 2.