You may see that additional home directories are not appearing as an option in Rearrange Account page in WHM, or you may see the following.
New mount point: The user is already installed on the only usable partition on this machine.
Additional home directories must be mount points (as in their own filesystems). Directories existing under the / filesystem will not be considered for placing accounts on.
The directory can be set in the "Enter the location where you wish for new users’ home directories to be created" setting on the following page of WHM. Before doing so, you should ensure that any existing home directories will be matched by the "Additional home directories matching the following value will also be used for new home directory creations" setting on the same page.
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