A topic from AEG's L5R CCG Rules forum, copied for Oracle of the Void from a copy of the forum saved in October 2015, so pages it didn't save are missing. Players' names are left out; the rules officials are named. Rulings are as they stood on these dates; later rulings, the rulebooks and the Rules Archive may differ.
A player, 23 July 2008
Suppose I'm playing out of the Eastern Hub Port stronghold.
I have a personality outside of a battle and I attach Hidden Reserves to him. Does he get to move to the current battlefield before I get my additional action or do I have to take my additional action before the movement occurs?
Hidden Reserves: Battle: If there are any enemy units at the current battlefield: Attach this card from your hand to your target Personality at any location. Move him to the current battlefield.
Eastern Hub Port: After the first Battle action resolves each turn that attached a card to one of your Personalities: You may take an additional Battle action.
Thanks,
Brook Cunningham (rules official), 24 July 2008
Suppose I'm playing out of the Eastern Hub Port stronghold.
I have a personality outside of a battle and I attach Hidden Reserves to him. Does he get to move to the current battlefield before I get my additional action or do I have to take my additional action before the movement occurs?
Eastern Hub Port's trait triggers after the action that attached something resolves. Hidden Reserves' action doesn't finish resolving until after all its effects have activated, including the movement.
http://rules.l5r.com/Glossary_R#Resolve: "An action or trait... stops resolving when its sequence of effect activation has ended".
So, you receive your opportunity to take an additional action after the movement.