I've worked on documentation for one of our open source projects using the All Users visibility and editability policy. As it's finished, I want to migrate the project page and all of its subpages from All Users to Public visibility and a project-based editability policy so it's available to the public, but can only be edited by trusted users.

This is a daunting task currently, with me having to go through all of the subpages one by one and edit their settings, which is both tiresome and error-prone. A solution such as T6004 would be great.