So thanks to the breaks created by the author we now have known in existence a level 9 and 8 at the same time (Hera and Zeus captains) and they had at least one level 7 each as well.
Loki has hit floor 59/70 and we now have that the previous strongest familias lied about which floor they hit.
So my thinking is that the current strongest two (Loki and Freya) familas are no where near as strong as either Zeus or Hera familia at their height, with only what like 4 months till the end of story and the dungeon should be "beat", the only current first class people that could theoretically level up are; Finn, Riveria, Gareth, Ottar, Allen, Hedin, Hogni, the quads, Bell (obviously).
This would give Loki 3*level 7's and 4* level 6's and then Freya with 1*level 8, 3*level 7 and 4* level 6 (5 if Mia comes back) and then whatever level Bell is at.
So the only way that I can see this dungeon being finished is if these levels happen and then we get a co-op between Loki and Freya to complete to the bottom, that gonna be very interesting to read.
My thinking is that bar the 3 quests Zeus and Hera never did co-op dungeon dives so this division meant they couldn't achieve the bottom floor on their own.
Alternatively Bell reaches level 10, powers Argonaut for 24hours straight and punches the roof of babel down into the dungeon destroying it and anything that exists inside.