That will allow you to still work on the "bad" array, once that's restored, then you can just move the other array back.  You need to keep the original drives in the original chassis to keep the support records straight.  There are only a couple of things that will keep an array down for very long.  (excluding environmental issues).  Failed chassis, very, very rare, which we stock in area depots and completely failed raidset.  Everything is fully redundant.   With chassis replacement, move drives, CMs into new chassis and power it back up.   With faulted beyond recovery scenarios,  that could involve recreating and restoring.  Which takes time.  So having the other complete array running allows you to do that.   Once restore complete move to that member and move the other array back to the dr site. 
Hello, We have two PS6000X SANs.  One is used for a production environment, and the other is use for our corporate data.  They are connected via a WAN link that allows for some volume replication, but we can't fully replicate the SANs, both because we need more space than that would allow, and because the link between the two is not that robust. So, in a disaster sitation where the production SAN's chassis fails, and we will be down for more than a day, is there a procedure that could be followed to place the hard drives from the production SAN into the other one, and get it working as if it was the same.  The SAN's are in separate groups.  I understand that the group configuration can be saved and restored.  So would it be a matter of restoring the group configuration from the production SAN on the other one, then inserting the hard drives and spooling it up?  Thanks.
Transferring hard drives from one PS6000 to another