42 players in the HQ area.
Divisions/classes, gear, equipment is all selected here.
It is the main thing multiplayer loads into (aka destiny tower)
Teams can be created here and loaded into matches.
While matches are being loaded you can still move around the HQ.
There's activities to do in the HQ like firing range challenges, 1v1 in a pit amongst other things.

Abit on War: It's 6v6 with objectives that have to be completed to push forward. Examples given: escort tank over bridge through city street, take out AA gun in enemy stronghold. It rallies back and fourth (reminds me of a similar thing to BFOne Operations)
Quick pic of firing range from the HQ:

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