Assault in Capathia: 3+ min
Assault in USS Regan SeaBase: 3+ min
Assault in Albyn: 3+ min
Total Observed Battles: 6
Observed battle type for current war:
Someone posted an interesting thought the other day on the Ubisoft forums...
My guess, is that when UBI modified the Victory Conditions inf the Theater Of War(no more 3 capitals at once), its Unlikely, that they changed them in the Trophy Criteria. (Referenced April 23, 2011)
This change did happen after the first or second war. The criteria for victory was once 3 capitols instead of 2. So when UbiShanghai changed prerequisites, the achievement may have been affected adversely by it as well.
I see this as very possible. But I'll continue testing my final theory until I can disprove it as impossible.
I'm going to assume that this is a new war since it's on turn 52.