Existing redirects are those that serve strictly as a move from a previous existing page to the new location. These redirects typically have no significance and are generally used if the page being moved has been on the wiki for a long time and might have links (internal and external) pointing the old page that haven't (or can't) be fixed.
Example: Alvin and the Chipmunks Film → Alvin and the Chipmunks (Film)
Pages in category "Existing Redirects"
The following 39 pages are in this category, out of 39 total.