The method I’ve seen is to change the output path. The playblast output is set in the shots blend file. Then you use background/command line rendering either manually or thru batch script to do final renders. Side note: the option is
-o or –render-output
Followed by path and file name. No space in the path or file name. Use. Double forward slash(//) at the beginning to denote relative to blend file. Additional note: Blender options are case sensitive. So O is different than o.