If you check back a few months, maybe four month, not really sure hopw long ago. But in the HTC update info forum, you will find where they said something about bringing in ground troops.
Where as you could be a paratrooper and storm the map room, or you could be a defender at the map rom. I also beleive it said that the fight could take place inside the map room, as where you had to run down hall ways to make the capture and could fight there. now I have not look back to see what it said exacty, but it was some thing along this line if I am right.
It would be best to go back and check for your self what it says. get all the right info and not what I can remember from then.
either way, it should be fun when it all comes together.