Edit: Ignore this post, looks like I was wrong.
I was running the Grey campaign for the first time since the latest patch and noticed that when I arrived in Moorland Trenches, there were only two factions, grey and brown. We each seemed to have about half of the map (though brown may have had more) and green was nowhere to be found. I later did manage to find a group of green soldiers in East Town that had surrendered. They must have spawned in when the map started and then immediately surrendered because they had no bases.
I think the bug has to do with the fact that the original (green) campaign start you off with a single base and with grey and brown fighting over the rest. I think this may not have translated to the grey campaign and instead gave the player faction the role of what would have been a non-player faction. I hope that makes sense?
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