Nikon Japan temporarily suspended orders for the Nikkor Z 100-400mm f/4.5-5.6 VR S lens because of a “large number of orders which exceeds our expectations“.
The Nikkor Z 100-400mm lens is currently in stock at:
Expect availability to become limited in the coming weeks/months.
Here is the Google-translated notice from Nikon Japan:
Notice Regarding Temporary Suspension of Orders for “NIKKOR Z 100-400mm f/4.5-5.6 VR S”
December 01, 2022 Product information
Thank you for your continued patronage of Nikon products.
We have received a large number of orders for the “NIKKOR Z 100-400mm f/4.5-5.6 VR S”, which exceeds our expectations. We have decided to temporarily stop accepting orders from Friday, December 2, 2022. We are considering increasing production due to the favorable reception of orders, but we sincerely apologize for causing a great deal of inconvenience to customers who are waiting for this product.
We will continue to monitor the situation and make an announcement as soon as it is confirmed.
We will do our best to deliver it as soon as possible, so we appreciate your understanding. (source)