Nikon has some new rebates for the month of May in the US – they now include the D850 again, the 200-500mm lens, and a few other F-mount lenses:
The previous Z discounts remained unchanged as far as I can tell. A total of 63 cameras and lenses have a discount – see the details at:
Amazon also has an exclusive sale on the NIKKOR Z 24-120mm f/4 S lens (18% off):