Delete old versions when disk is full

[mlage]

In "Sync Settings\Sync\Delete files" I didn't find any option to delete old file versions when disk is full. Is that feature available anywhere?

Here are more details: I am planning to use FFS in a workstation used by multiple users. This is our backup plan:
D:\ - work area
F:\Backup\Latest - location where we want to mirror work area (detected moved files is turned on)
F:\Backup\Versions - location where we want to keep old versions (file names with time stamp)

But we didn't want to set a day limit for backups... we wanted to backup as long as disk space was available. When disk is full, we wanted FFS to start deleting old version files.