I've noticed with several anime that are adaptations of manga or novels that the first episode is based primarily, if not entirely, on content from several chapters into the story. Such shows will usually jump back to the actual beginning of the story near the end of the first episode or episode 2 will go back to the start and all episodes will then progress normally.
This is unrelated to any major or minor changes in characters, plot, events, etc., I'm just talking about the general use of later content for the first episode before jumping back to the beginning afterwards.
Typically, I can't think of any other examples off the top of my head, but Kuma Kuma Kuma Bear this season has done it which is why the confusion and annoyance has prompted me to ask here.
The way they've done it for Kuma Kuma Kuma Bear is especially frustrating as they dropped several short "flashback" scenes throughout the episode without much context and which don't have any relation to the actual content used for the episode, and they imply that the core concept of the show could be very different than the manga or novel. Now we have to wait for episode 2 to hopefully clarify that. I may just be overreacting on this point, though.
Also, I wanted to add the tags
kuma kuma kuma bear, and
first episode but none of them exist and I don't have 300 rep so I can't create them. I wouldn't really say that
anime production fits my question, from the description that accompanies it in the tag input thing, but it's the closest I could find seeing as I'm not allowed to post a question with zero tags ¯\_(ツ)_/¯