Suppose then you have an story in your mind. Then, to write down this finite series of events, you have to translate your imagination into the paper. This process isn't trivial, of course and plot are just one of the "underlying structures" you may want (or, in most of the cases, should have) to use.
Now, again, suppose then you have an story in your mind; is the story of a hero(ine). You, then, write your story with the aid of, for instance, Blake Snyder beat sheet  and nothing more.
Now, by definition, you have a particular plot structure on your story. But, as a some sort of "definition" of a hero(ine) story, you can in fact point out a hero's journey plot structure as well (I think). So, the writer used  but the story also have, "canonically", the hero's journey structure.
My question is: suppose that you have a story which you wrote with the aid of a plot structure A. But you realize that and another plot structure B could be used as well. The story must be independent of plot structure (Just like a physical phenomena must be independent of reference frame)?