I love this thread. Very insightful.
When I began making Starmada (which is a 3 season serialised 5-8 minutes episodes. 9 eps season 1, 10 season 2 and 14 season 3) I wasn't aware of this formulaic script writing. I assumed a story needs a beginning, middle and end logically.
Having looked back I see each season as an act. The limitations of the animation studio I used made it necessary to make it in mini episodes. Ideally I would have liked to make 20 minutes parts of 5 episodes per season. However, it has taught me an awful lot about creating cliff hangers- especially ones which seem to have impossible resolutions.
I feel like I have followed the 3 act plan . Introducing the enemies and main characters in the 1st season. Revealing the mystery and adding complications in season 2.
In season 3 I do wrap things up- however I feel like with this season the 3 act plan is used again throughout the season. I decided mid season to tell the story in flash back for 3 episodes.
I don;t know if this has broken the rules but I think it added an extra element and kept the storytelling fresh and unpredictable. I was heavily influenced by 24 during season 2. Does 24 follow the 3 act rules? All I seem to remember is the show just building up more and more tension and mystery- not many revelations until end of season