3.1.1 Firmware Update

I’ve updated Drobo Dashboard (2.6.2) and the Drobo Firmware (3.1.1) and now my Drobo will no longer connect over Thunderbolt. I can connect over USB and the drive appears on the desktop, but I have problems opening it in the Finder - sometime I can open it and see the contents, other times double clicking it does nothing.

I’m running a late 2013 27" iMac with Mac OS 10.10 DP7. Drobo and Drobo Dashboard had been working fine on this OS release prior to updating.

I have updated Dashboard (2.6.2) but I am unable to complete an update to the Mini of (3.1.1). I have tried a manual update per instructions and I have tried both thunderbolt and USB 3.0 cables.