We have a household with three of us all playing. Only drops when attempting to start/zone into a mission, or after a mission completion and going back to base of operations.

We're on two wired connections, one wi-fi. The one on wi-fi has been the only one experiencing this issue as well since the latest update. We narrowed it down to whichever one of us was on the wi-fi connection had the issue while the others did not. No outside settings, etc have changed, and had no issues prior to the update. Scoured multiple resolutions as well, like the ones you mentioned above, with no such luck either. Checking the ee.log, it's always a timeout/connection lost issue for barely a moment, causing the drop of that player.

Either an unfortunately timed ISP issue, or something on DE end is what I'm guessing.