Changing linked pages automatically

Hello everyone, my question is this, I have a file where I insert links that contains two or more pages, and then I relink with changing, for example from page two to page three, there is a way to do it automatically, how to identify within a script which use to be relink page, noting that the page on which I refer could be a PDF with more than two pages where before was page two of the PDF link and then the page will be three

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