Custom File Name At Start-up Using Macro-Enabled Template Format (.XLTM) (VBA)

So I am trying to make a file that when opened will act as a template does and change the file name on start-up.

Typically, the template changes the file name by appending one number (e.g. "Book Template REV 1.1.xltm' upon opening would change the file name to 'Book Template REV 1.11.xlsx'). What I want to do, however, is to custom the name change so I could use the file 'Book Template REV 1.1.xltm' while having it change the file name upon opening to 'Custom Name 567.xlsx', without a user being notified of the change (since typically when a template opens the file, the user has no notification that the file name has changed ever so slightly).

Any thoughts on how to approach changing the naming scheme for a .XLTM?