• Summary / Title: Multiplayer with AI turns never ending / AI never passing
• Description: I played a multiplayer game with a friend, and struggled past turn 100. The AI would consistently stop passing their turn. A save and a reload often helped fix this, but we simply could not get past turn 120. Every behaviour about the game had a slow response past turn 100. Ships would struggle to move, sometimes anomalies wouldn't scan, we couldn't get confirmation of actions to occur correctly. These are all actions that could occur within a turn, but the end result is that the turns could not continue.These were not regular desyncs, we just could not progress.
• Steps to Reproduce: Unknown what caused the issue precisely, theories are in the Notes section
• Reproducibility: ?/5
• Expected Behavior: N/A
• Version: 1.5.11 S5 GOLD-Public
• Notes: My friend and I play with some distance between us - England vs Australia, so some extra latency might have been an initial cause. I struggled to draw patterns with what was going wrong, but the only thing that consistently came up was the Umbral Choir. When AIs had not passed, it was consistently them. Occasionally the game did resume after a delay, then popping up a talks dialogue with the Choir. Indeed, when the Choir had not passed, their AI bubble was listed as "In talks". We were also in an alliance with the Choir for some of this. We have since played games successfully by disabling the Penumbra expansion, and playing with everything else on. This has been much smoother.

I am attaching the problematic save file. I was playing as Horatio, and my friend was playing as the Vaulters. 

Second-2.sav