Chain of Command Detachments with the Chain of Command special rule can only be issued an Advance Order unless instructed otherwise. If an Independent Unit contains only models without this rule, then that Independent Unit can be issued another Order, even if the larger Detachment can only be issued with the Advance Order.
Forward Deployment After both players have deployed their armies, including Infiltrating Detachments, but before the first round of the battle, if all models in a Detachment have the Forward Deployment special rule, the Detachment may make a special move.
The controlling player can move each Forward Deployment Detachment on the battlefield up to a number of inches equal to its Movement characteristic, ignoring Difficult terrain and Dangerous terrain rules. This move can the Detachment outside of its deployment zone and a Detachment can Garrison a Structure if they are able to.
If both players have Forward Deployment Detachments, then the winner of a roll-off chooses who moves their Detachments first.