Overwrite original PDF

We are using your app as a part of our documentation workflow on our Samsung galaxy tabs.

In our documentation App we have PDFs (with a local file copy on our tablets) we want to edit.

However, when we are importing them to Notewise and edit them, we have to export the file to write a native PDF (with annotations burnt in)

Is it somehow possible to export/replace the originally imported PDF file? Basically a "save/overwrite" button.

Seems like our folders where the app has stored the files is not accessible via android file manager.