Failover of FS7610

We have two FS7610 NAS devices.  They are not configured as a cluster, instead the FS7610 at our production site is replicated hourly to a FS7610 at our DR site.

In reading documentation on these devices, I see information talking about a failover to a 2nd controller.  And I'm pretty sure they're talking about to the 2nd controller in the FS.

Is there any documentation that lists the steps to follow to failover to a 2nd FS, in our case our DR FS7610?