When does NVC start further processing?

[N4329M]

I would like to ask a short question here.

My wife’s family based immigrant petition is waiting at NVC and becoming (hopefully!) current within 6 month based on the July-Visa-Bulletin.

I read "When an applicant’s case is about to become current (a visa number is likely to be available within the year), the petition is forwarded to the appropriate U.S. embassy or consulate overseas." In our case, it will be in Germany.

Question: When can we actually expect further processing?

Thanks for responding!