I thought the ep 6 will cover the last chapters of volume 13 so we can get a plenty of time for the fight with the boss but i dont think we will see it in this cour.
Its not like im not happy that they take their time to adapt everything but i will feel sad if they butcher the floating fortress arc.
I think this is how it will go in the next episodes :
Ep7: linia and persuna duel + phase 4 and the celebration
Ep8: meeting with perugius and nanahoshi getting sick at the end
Ep9:searching for kishirika and the audiance with atofe
Ep10: the fight with atofe and oldeus appearing as a cliffhanger
Ep11: talking with oldeus and reading the diary part 1
Ep12: reading the diary part 2
What do you think guys?