I think what the users above are beating around the bush by asking about next steps is: if the patch doesn't fix the issue are we going to have to wait another 2+ month period before we see results? And in that 2+ month period are we going to get more empty responses, vague answers, and finger pointing at Microsoft or Focus before Larian gets in gear?
...Or are we going to actually get some substance?
Rant you can ignore:
I got a refund on my Steam copy because of false/ambiguous statements about cross-platform play. In a bout of poor judgement I decided to give Larian a second chance by buying an Xbox1 copy. Now I am experiencing the problem described in this 8 page thread. Co-op hasn't worked on three different platforms now. SteamOS, PC and now Xbox One. (granted for differing reasons per platform, but the end result is the same: broken.) Clearly there was little or no quality control in regards to the game's most advertised feature, Co-op.