I just had a thought.

Let's say that this is only rarely occurring not by choice, but by necessity.

When you lose connectivity there will be likely be a small window during which the server isn't responding.

What if you were monitoring the network, and when you see a loss of connectivity you spring into action, responding to the reconnection request pretending to be the other server?  Spoofing/monitoring is a pain, and besides once they reply again then things are going to get messy.  So the very first thing that you do is redirect to your own (local) server (which also stops attempting to reconnect to the primary), then once the connected to you then you can redirect to the proper server without having to spoof or monitor the network.

If this isn't triggered, and only happens during a natural disconnect then it would explain why it happens to so few people.

Perhaps people can try to intentionally cause a disconnect from their primary server, momentary firewall rule or just rebooting your gateway could do it.  See if anything attempts a redirect?