The Nikon Nikkor Z 800mm f/6.3 VR PF S lens is rumored to be announced this week

I still do not have the exact date, but I believe it will most likely be on April 6th (it could be earlier):

Updated Nikon NIKKOR Z lens roadmap (January 2022)

Nikon’s presentation at the 2022 CP+ show: Z9 cat meow custom shutter sound and hands-on with the Nikkor Z 800mm f/6.3 VR S lens

Updated Nikon NIKKOR Z lens roadmap (January 2022)

Nikon Nikkor Z 800mm f/6.3 VR S lens development announcement