https://forums.whonix.org/t/whonix-host-operating-system/3931/6
Disk size issues: We don’t know how big the target device is. A 16 GB stick (we only need perhaps 4 GB) or 1000 GB USB hard drive. We have --vmsize but what size do we select for default download users? I remember netrunner-odroid has a script “on boot, expand my parition to maximum size of this boot drive”.