I see, that makes sense.
I still can't wrap my head around that while playing. I looked into seals, and it had already all the time limit increases. I also gave it another try. It didn't go well. Basically one whole side of the dungeon was empty, and despite trying to speedrun it the time run out some distance into the second wing before I managed to find anything. Is one of the wings always supposed to be optional? Is it possible to determine that before wasting time?