> Third, you don't change the article in any way. You don't use a piece of it, and ad you own comments. you paste the article on the page with an appropriate byline
This has never been how AP works. Where are you even getting this stuff?
AP traditionally provides stories in an "inverted pyramid" [0] structure, such that an outlet can use as much or as little of the story as they need to fill a given space on the page.
They're free to modify the text as much as they want to. Such an article will list the Associated Press and whatever journalists edited, contributed, or otherwise mangled the original article. My (least) favorite modern example of this is when the Fox News website takes an AP article that makes the Republican party look bad and adds or subtracts to it until it's less damaging. The people responsible for that mangling are listed as contributors to such an article, as is the AP.
[0] https://en.wikipedia.org/wiki/Inverted_pyramid_(journalism)