Ubisoft - It would really help for you to explain what the hold up with this. We deserve a thorough explanation for why this is taking so long to resolve.
I struggle to believe this is so hard to narrow down and fix. There has to have been a limited number of relevant changes submitted into your source control system, it cant be that hard to go through those changes.
The fact that this is taking so long suggests something is really wrong with your development process, or that you just don't give a damn. Given the nature of your (lack of useful) communication, I have to suspect the latter and given the nature of your buggy releases, it seems the former is a significant contributing factor as well.
You owe your customers an explanation along with compensation for a significant portion of this game being effectively not available to many of your customers for an extended period.