Rundancy issues after updating from 8.1.47 to 8.3.0

I have upgraded Ignition on my master and backup server from 8.1.47 to 8.3.0.

First of all, in the diagnostic window when I click configure as illustrated below I am sent to the home page:

My main question is as follows:
I have set up my network card 1 on both servers and added hostnames in the hosts-file according to IP-address in network card 1. IN my gateway I have added hostname in my network binding interface for both gw’s and set “auto detect network interface” to false.
I opened a Perspective session in my web-browser and then turned off Ignition GW for server 1. As expected I was the automatically redirected to a session on backup server.

After this I added Internet on network card 2 and remote desktoped my way in to my master server and did the experiment again. This time my session was just ended without beeing redirected to backup GW. Since I specifically added IP-address for network card 1 in the network binding interface in redundancy settings I thought I could use my other network interfaces for other purposes. Why did this happend? Why did not my session automatically swtich over?