File Naming Conventions

Filenames should not contain date information or version information. If possible it's best to keep it the same name and use the /admin/content/file section to replace the existing file (screenshot).

If you try to upload a file with the same name while editing content pages, the file will be renamed with an appending _0. (screenshot)

So keep file names the same and update the link text to indicate it's date. (provide further demonstration) Additionally, there are usually ways to add version information within the file in a header or footer or even in metadata.

The benefit is that if another site should directly link to you file resource, that link would continue to work. if you change the name and and don't delete the old file, that direct link would still work and no one would know it's not the correct version of the file.