Okay so ... in the OOC i put where everyone is starting under each faction section. Marines you'll be starting with the captains and their companies in the upper hive... Preparing rites etc before you go to mid hive. 

Guardsmen are obviously with the regiments down in mid hive already preparing defenses now that the drop pod marines have pushed back the chaos forces.

Inquistion you are in the mid hive with the guardsmen doing whatever the fuck inquisition wanna do xD