In the latest build, new feature has been added to the Unattended page, the ‘Disk partition configuration’.

It goes without saying, be very careful using this feature.
Depending on what you select, it can wipe your disk clean, create and format partitions, and install Windows to a partition without user interaction.
Let me highlight it again, these options can erase your disk by simply booting the image if you set it up to do so.
Of course people who requested such a feature will welcome it, as it speeds up deployment.

A lot of work went into the implementation, to be simple as a few clicks to setup while magic happens in the background, so it is for licensed users only.

If you get an error 0x80042565 during the initial Windows setup phase, that mostly means the auto-partition type was set to GPT (UEFI) and the setup was booted in MBR (BIOS) mode, or vice-versa.
Make sure those two are in sync, auto-partition type cannot be universal between UEFI and BIOS due to different partition schemes.

Enjoy, and be careful with the wipe option.