We are aware that the number of reports of this issue has greatly increased since the release of Choose Your Own Apocalypse. A disconnection (Error Code 3) or an attempted reconnection that times out (Error Code 4) seems to be a barrier to some people.
We have isolated a few areas of concern and will be performing some network optimizations as we continue to support the game.
In the meantime, we suggest trying to ensure your connection is as strong as possible and use direct connections to your router or modem. People with stronger connections seem to experience the issue less. Once you start experiencing the issue, we also encourage you to close the game and relaunch before attempting a reconnect to the host.
UPDATE: We have isolated one source of the problem. We are thoroughly testing the fix to ensure it does not have widespread effects. We apologize for the delay, but hope to have this out to you soon.