Unsupported Partition Layout

I don't expect anyone to know the answer to this question but I'd like to understand what might have happened.

I have upgraded my license and added an additional drive, in order to add the additional drive, I had to re-route some Sata and SAS cables, as one SAS cable was in use on a SATA drive and I needed it for the additional one I was adding. The drive in question was the parity drive.

On plugging everything back in (this was done whilst server was running (but with array unmounted) as its a pain to get it to boot from USB), which I've done before with no issue.

On remounting the array, one of the drives was reporting Unsupported Partiton Layout, I have no reason to think this drive has issues or is drying, I have had to unassign the drive and then re-assign it for unraid to begin the rebuild process.

Here is the relevant info from the syslog. I now no longer have an sdb device listed, but it is now instead sdj

Mar 14 16:00:25 Tower kernel: sd 7:0:8:0: device_block, handle(0x000e)

Mar 14 16:00:26 Tower kernel: .
Mar 14 16:00:26 Tower kernel: sd 7:0:8:0: device_unblock and setting to running, handle(0x000e)
Mar 14 16:00:26 Tower kernel: sd 7:0:8:0: Power-on or device reset occurred
Mar 14 16:00:26 Tower kernel: sd 7:0:8:0: [sdb] Read Capacity(10) failed: Result: hostbyte=0x00 driverbyte=0x08
Mar 14 16:00:26 Tower kernel: sd 7:0:8:0: [sdb] Sense Key : 0x6 [current] 
Mar 14 16:00:26 Tower kernel: sd 7:0:8:0: [sdb] ASC=0x29 ASCQ=0x1 
Mar 14 16:00:26 Tower kernel: sd 7:0:8:0: [sdb] 0 512-byte logical blocks: (0 B/0 B)
Mar 14 16:00:26 Tower kernel: sd 7:0:8:0: [sdb] 0-byte physical blocks
Mar 14 16:00:26 Tower kernel: sd 7:0:8:0: [sdb] Test WP failed, assume Write Enabled
Mar 14 16:00:26 Tower kernel: sd 7:0:8:0: [sdb] Asking for cache data failed
Mar 14 16:00:26 Tower kernel: sd 7:0:8:0: [sdb] Assuming drive cache: write through
Mar 14 16:00:26 Tower kernel: sd 7:0:8:0: [sdb] Spinning up disk...
Mar 14 16:00:27 Tower emhttpd: device /dev/sdb has size zero
Mar 14 16:00:27 Tower kernel: .
Mar 14 16:00:28 Tower kernel: .
Mar 14 16:00:28 Tower emhttpd: device /dev/sdb has size zero
Mar 14 16:00:28 Tower kernel: .
Mar 14 16:00:29 Tower kernel: .
Mar 14 16:00:29 Tower emhttpd: device /dev/sdb has size zero
Mar 14 16:00:29 Tower kernel: .
Mar 14 16:00:30 Tower kernel: .
Mar 14 16:00:30 Tower emhttpd: device /dev/sdb has size zero
Mar 14 16:00:30 Tower kernel: .
Mar 14 16:00:31 Tower kernel: .
Mar 14 16:00:31 Tower emhttpd: device /dev/sdb has size zero
Mar 14 16:00:31 Tower kernel: .
Mar 14 16:00:32 Tower kernel: .
Mar 14 16:00:33 Tower kernel: .