Audit Mode is practical when you want to customize Windows and relocate Users folder already before any user profiles are created, entering Audit Mode from last phase of installation (Method One) and doing it there because Audit Mode is the only way to use Windows normally without having any existing user accounts.
When Windows is installed there's no need to go to Audit Mode and in any case you cannot upgrade when in Audit Mode. In my case now I moved all personal data from various user folders (documents, images, videos and such) to an external drive to make the profiles as empty as possible to make relocating faster, then run the Sysprep with this command from an elevated command prompt to move Users back to C::
(The answer file relocate.xml with instructions to Sysprep in drive X:)
%windir%\system32\sysprep\sysprep.exe /oobe /reboot /unattend:X:\relocate xml
Then to tackle the "Sysprep - Upgrade paradox": an upgraded Windows cannot be sysprepped, a sysprepped Windows cannot be upgraded, I needed to edit one value in registry to allow upgrading a sysprepped Windows. Download and install Build 9860 upgrade, again registry editing this time to allow an upgraded Windows to be sysprepped, and finally Sysprep to move the Users back to E: where I want to keep it.
All in all, I needed a bit more time than a system where all system folders are in default locations on C:. In my case this whole operation took two and half episodes of the Big Bang Theory from Netflix , about three times the time Lee told was needed.