Canon RF 200-500mm f/4L IS USM confirmed, likely in Q4 [CR3]
Amazon.com : Tamron AF 200-500mm f/5.0-6.3 Di LD SP FEC (IF) Lens for Canon Digital SLR Cameras (Model A08E) (Discontinued by Manufacturer) : Camera Lenses : Electronics
Amazon.com : Sigma 200-500mm f/2.8 APO EX DG Ultra-Telephoto Zoom Lens for Canon DSLR Cameras : Camera Lenses : Electronics
We Review the Canon RF 100-500mm f/4.5-7.1L IS USM Mirrorless Lens | Fstoppers
Canon EF 200-400mm f/4L IS USM Extender 1.4x Lens Review
Used Nikon AF-S Nikkor 200-500mm f/5.6E ED VR | MPB