replication manager failover/failback on a VNXe 3100

Hi, i am currently testing RM 5.4 with 2 VNXe 3100.

I have set up an iSCSI LUN that i am using for VMFS replicated between the 2 VNXe. I wanted to test failover/failback so i selected the failover option in RM, and pointed it to a proxy host on my DR ESX server.

The failover worked perfectly, making the original source LUN read only, and mounting the target as r/w to my DR ESX server. Now i want to test failback but this is where i am having problems.

There doesnt appear to be a failback option.. How do i go about failing the volume back to my primary VNXe?