Its ODD. Sometimes the App does it backwards (and prior to the recent update, it depending on the settings you had based on the series you watched prior). I guess they want you to see what episode's currently up and see how things may entice you (it especially works for anthologies and short-form works like Comic Strips.)
I think for Novels and story-based Comics, there should at least be some kind of better outlining section where if you have a series with multiple stories, you can just click on the initial series, then Tapas will have an outline of all the mini-stories/episodes lined into proper categories. There it would tell how many chapters are in a certain episode, how many words are in each work, and label the inner stories from Episode 1 to your latest one. That way Tapas can distinguish what works are just singular one-shots, and which stories are ongoing. Here's an example of what I mean:
Something similar can work for the mobile app too, but that system already delivers a barebones version of what I'm getting at here with every chapter being labelled as an episode regardless of the context of the story being told, but it isn't really concise as I would have hoped. Hopefully somewhere in their infrastructure, they can do something like this rather than focus on... I dunno. What are the staff up to anyway?