What if KanColle Kai was a RPG game such as Breath of Fire, says the commentary.
BoF is known for having formations able to surpass the three members (normally the top being 4 party members at the same time). I guess the artist is trying to mimic BoF IV, where despite having a fixed three member party per battle there's actually a second back up row where characters can switch to the front row if needed (and regain health when being in the back).
I guess I'll add some more tags to the picture like the gameplay_mechanics, breath_of_fire (even if it still looks more like Suikoden I & II with two active rows, in BoF IV Tenryuu, Murakumo and Kaga would only be shown in the HP bars on the bottom of the screen unless when switched... like Tenryuu who should be replacing one of the active three) and of course the myoukou_pose.
.P.S.: That was kinda of a draggy speech, but couldn't help it... I'm quite the RPG nerd...^^U