This information is still being confirmed. They don’t know if this will be an official announcement for the general public or an internal announcement for retailers. Nikon Z9 is already on the site at some European retailers (these retailers are known to get official information from Nikon before creating a product list).
If Nikon Z9 is announced tonight, it will start shipping from the end of October to the beginning of November, but because of the global shortage of parts, the waiting time is expected to be very long.
In other souce, they heard Nikon Z9 announcement is on October 13th.
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