About a month back, I updated the Unitrends Agents on all of my servers to the latest version. This included 3 of our Hyper-V 2008 R2 hosts in addition to 4 Hyper-V 2012 hosts. These hosts comprise two clusters (2008 R2, and 2012, respectively). After updating the agents manually on the hosts, the client nodes in the Unitrends Recovery Console show the correct updated version (7.1). However, the Hyper-V cluster nodes do not.
I know how to fix this and have fixed it on two of our three Unitrends 813 appliances. The fix is to go to Settings > Clients, Networking, and Notifications > Clients. In clients, the affected Hyper-V Cluster Client needs to be selected, then the client configuration needs to be re-saved (without modifying any settings) by clicking the Save button.
Since I know how to fix this, I'm not inclined to contact support. That said, I think this may be a bug that should either be documented or fixed.