I won’t try to dissuade both of you from your beliefs, but you are both wrong but you should contact WD Tech and file a support ticket.
My Cloud Home is OS4 and it is not OS3 or OS5, it will never be OS5.
Your thread was already answered. Local connection is not always persistent, depending on ISP, router and WD authentication server condition.
If you have 8 TB and you only have 12 GB free, that is the definition of ‘Storage full’. The OS will easily use up 12 GB on swap file and indexing.
