Crate have made it clear for some time that there’ll be no more expansions for the game. They’re focused on their other projects: Farthest Frontier, a town building game with optional combat due to go into early access on the 9th August on Steam. More info here
and Crate will be doing a live dev stream of the game this Friday.
They’re also working on a horror survival game plus an RTS game which we know will be set on Cairn in a pre-GD era.