Anyone else having the same problem. @James Kindon provided a workaround, 1. Change your paths as follows (add the %username%_%sid% variable).
• type=smb,connectionString=\\PATH\%username%_%sid%
• type=smb,connectionString=\\PATH\FSProsper\%username%_%sid%
2. (OPTIONAL) Enable the FSLogix Setting NoProfileContaingFolder which is “No Profile Containing Folder” in the GPO Configuration Settings This will make it so that you don’t create a \\PATH\%username%_%sid%\%username%_%sid%\*.vhdx scenario and maintain a \\PATH\FSProd\%username%_%sid%\*.vhdx scenario. This is for consistency rather than functionality, as we are focused on the TLD being per user (the %username%_%sid% portion). This is what allows us to distribute load across multiple FSVMs. If you are happy with an extra folder in your path (extra depth) then you don’t have to enable this.
3. Set FlipFlopProfileDirectoryName back to Disabled in the GPO which is “Flip Flop Profile Directory Name” as it’s no longer relevant as we are creating the %username%_%sid% folder as the TLD Configuration Settings.