Clearing [Perfect Attack Boot Camp VI] grants you Io's partner card. However, you get both versions of her at once. Episode 4 is not released yet.

No problem, Pietro is an episode 4 character too

Naturally. In this case though Io is an Episode 2 character. Pietro and Summoner were specifically integrated with EP3 content. So that's normal.

Once again these things don't matter a lot. It's just my duty as a player to report small things.