Re: [Question] How is the lv. 12 BP Point Boost calculated?

1. Yes, the xp boost is only active when you start a game with a pre-made party. They don't need to be your friends, i've played with 1 friend and 1 friend of a friend who wasn't on my friends list and the bonus activated for both.

2. The term 'stacking' means across all unlocks you have. For example if you reach level 22 you will activate 2 xp bonus' for having the level 12 unlock + the level 22 unlock, these are what stack, It doesn't stack across people in your party.

Hope this helps.