I have 4 array disks installed in Akitio NT4 USB enclosure which connect to my N5095 mini PC, they work perfectly well in 6.9.2 except no S.M.A.R.T. info available.
However in 6.10.x and 6.11.x versions, these disks are not able to spin down correctly.
I could spin them down manually, but only in seconds they would spin up again.