I have taken the time and watched the announcement video from ModCon on Twitch:
Video Link
Matt Forbeck apparently had a script for the continuation of the Venusian Apocalypse Campaign (this campaign for MC3 was already published quite a while ago, and it was originally published for Mutant Chronicles 2 decades ago).
This script was supposed to be for a graphic novel. But Modiphius wants to publish it as a roleplaying campaign for MC3 with the title(?) “Dark Eden”.
But there already is a Dark Eden Campaign for MC3.
So I am a bit confused why the new campaign has the same title as the old one.
Due to the new campaign being the continuation of the old Venusian Apocalypse, the Venusian Apocalypse gets reprinted (if I understood that correctly), as it is the lead to the new campaign.
And for the boardgame “Siege of the Citadel” there will be a RPG campaign for MC3 where the players can play the iconic characters from the boardgame in a roleplaying campaign.
That is, what I took from the video I’ve linked above regarding Mutant Chronicles.