all those 26 chapters can fit perfectly into one season of 24 episodes with 2 OVAs or Specials, they completely botched the work when they decided to do it like this, there is a lot of material in the manga, if the stretched things a little they could even do 26 episodes
Edit:
I watched the episode again, because I didn't see some of the scenes earlier, since i knew this bit from the manga and was doing some cleaning, gotta say they deviated pretty far in this episode from the manga, I hope they didn't do it, but since nothing was really shown we shouldn't assume anything.
also, the reason why Saeko was fixing her skirt is, because she probably removed it for the night since it was probably also wet from water, so to dry it off over the night she removed it.
i don't understand why they shown so many zombies in the morning drawn in just by the leaves, looks like they wanted to follow the manga properly but this is completely wrong, and you will know later as they will show the reason for this, and why this should have been later in the anime, they completely screwed up the order of events. I watched the preview and I hope they will not jump the gun again
Edit2:
with the WET it was meant that she is so damn excited.
and now you know why we love Saeko the most, she is just kick-ass and superb, and the most normal person around
