Force traits, take 2 (L5R rules board)

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, 11 December 2007

During a battle, a Phoenix player 3 Shiba Miiko 's (Your Personalities at Miiko's Location have +1F for each Shugenja there.) , the Obsidian Dragon and 2 other shugenja at a battlefield. This gives the Obsidian Dragon 15F.

The opponent has Moshi Taya at the battle: "Battle: Exhange the Force of one of your target Naval personalities with the Force of a target Personality opposing him." Taya is also 2F and 2 PH -- meaning her force at the battle with Obsidian Dragon is 0F.

Then Taya takes her action targeting the Obsidian Dragon, with his 15F. So, her force is now 15, and the Obsidian Dragon's force is now 0.

Then the Phoenix player sends one Shiba Miiko home (with, say, Draw your blade). At that point the force bonuses would be recalculated -- because something affecting them changed. Does the Obsidian Dragon's force go from 0 to 6? Or does he stay the same? (I assume the other Phoenix personalities all lose -3F.)