Constantly disconnected from lobbys with friends

[Snipe_Wizard]

Since around the release of The Lotus Eaters (update 36.1.0), I have been constantly removed from lobbys with my friend. It initialy started as losing connection about once an hour but has been getting progressively more frequent. At this point we are being disconnected if we are in a lobby together for more than 15-20 seconds. If we do manage to select a mission, the non host player loses connection about 75% of the time while it is loading. If we do manage to get into a mission together, there are no issues and everything works as normal until the mission ends and we are immediatly seperated in the post mission lobby. This issue happens regardless of who is hosting and happens with both public and friends only settings. This does not happen when either of us play with random players, only when we are together. 

We have tried setting ping to no limit, enabling and disabling crossplay, port forwarding on both our routers (with upnp both enabled and disabled), changing the udp ports in game, forwarding those new ports, verifying integrity through steam, and completly reinstalling the game. When analyzing network ingame both players receive the "all systems nominal" message. At this point the game is unplayable together as we spend more time trying to start a mission together than actualy playing that mission.