I did not see any other post about this, but excuse me if there is. I have played the original sins with a friend of mine for some time, and now we have played entrenchment twice together. Both times we have played, we seem to experience a de-sync at a somewhat random point. It usually happens right around the epitome of technology and when we've placed numerous starbases (leave us alone, we like turtling). There is no warning of this desynchronization, we just suddenly figure out that we are no longer quite on the same page as one of us rushes to defend the other and they have no idea why.

When it happens, we both continue playing none the wiser, but seemingly in our own individual worlds. For example, I will have taken over half of the map and on my screen my ally is either laying around doing nothing or making pitiful attempts to attack. Then one of us will ask each other why the other isn't doing anything, and it turns out they have already taken over half of the map themselves, and it is the other person getting destroyed/sitting around. Very odd. This has never happened before the beta, so I can only imagine that is the culprit.