You should not promise a DLC release in a certain month if its still in progress. That is piss poor media release. They said Oct knowing good and well a lot of things needed to be done, and we all know how they stick to their deadlines ;).
In every other game I play, when they announce DLC or an expansion with a deadline, that deadline is met. In fact they have the product finished months beforehand and often do a weekend beta test to get real player data and feedback. Then fully release no more than a month after a beta test weekend.
Don't make excuses for their poor planning and poor media releases. Deliver DLC on time, or don't announce it with a due date.