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That's not quite it. Plot Parallel is about comparing the A-plot and B-plot for similarities. What I'm looking for is how two or more installments are basically the same structurally, with just the details switched around.
As another example, you could say that all the Harry Potter books (barring the last one) are like this: Harry is at his unfriendly relatives' house, he gets out of there because of his friends or something magic related, he goes to school and witnesses the Sorting Hat ceremony, Harry and friends attend classes, eventually a new mystery presents itself, new minor characters are introduced, some Quidditch is played, some scuffle happens in the school, Halloween and Christmas are celebrated, the mystery deepens, something important happens before the climax, climax resolves most of the mystery (Voldemort is always involved somehow), the DADA teacher is somehow forced to leave their position, Harry and friends board the Hogwarts Express back home.
Edited by Namor21
A large-scale His Story Repeats Itself for the Harry Potter example, also serving as similarly-scaled Book Ends.
The Septimus example is a subverted mix of Redundant Rescue and Now, Let Me Carry You.
There's also Same Story, Different Names and Strictly Formula for when this is more a writer using re-using story structure that's worked in the past.
For example: the second and third books in the Septimus Heap series play out like this:
Book 2: Jenna gets kidnapped and Septimus has to go rescue her, but she turns out to be fine, and together they have to return home to stop his crazy older brother. After which, they work on curing a boat.
Book 3: Septimus gets kidnapped and Jenna has to go rescue him, but he turns out to be fine, and together they have to return home to stop her crazy ancestor. After which, they work on curing the townspeople.
What trope best fits this use of a repetitive plot structure?