Curious about campaign. How does this work?
Imagine a galactic Risk map split in different groups of planets.
In the center there are the planets 100% controlled by humans. In the left, planets 100% controlled by some kind of jedi Terminators. In the right, planets 100% controlled by the giant bugs.
In the 2 borders between 3 regions there's a group of planets not fully controlled by aliens or humans, who control a % of the planet that it's constantly changing. Each time some player completes a mission helps to increase the % of the humans.
So you can make missions on a few planets to fight robots, or missions in other few planets to fight bugs. You can select different isolated spots of these planets, to start them yourself or join players who already are there and ask for help. You can see the ships of other players in the orbits of the planet, deploying players or making some big attacks from the ship.
Depending on that progress shared by all players (which I assume it's tweaked in the backstage by the devs), at some point humans will 100% control the group of a few planets that are in one of the frontiers. That should unlock the next group of players, some reward to all players who contributed, maybe some story event and new planets (with their own biomes, maybe new enemy types, weapons, etc).
As an example, they announced that you'll be able to pilot mechs. So maybe they will be unlocked when players control one of these regions.