Hi,
We received status from Khoros today on this issue, it turns out we found a P1 bug that was introduced to the platform in one of the update releases.
Apparently when you are on the platform for some amount of time, the load balancer tries to handoff the session to a new node. When this happens, a bug has been introduced that drops some users, maybe all were not sure.
We were able to replicate and capture the behavior and Khoros and they have accepted the P1 bug and are tracking it down as soon as possible.
So our settings are correct, but they are dropping sessions.
I will update everyone as the status changes on this issue.
Eric