The upcoming Canon EF 70-200mm f/4L IS II USM lens and EF 70-200mm f/2.8L IS III USM lens will be officially announced in early June, 2018. This is now confirmed by CR.
According to CR, they are 100% confirmed on EF 70-200mm f/4L IS II USM lens, and 95% confirmed on EF 70-200mm f/2.8L IS III USM lens. The price and release date for both lenses are not available yet. Stay tuned for more info.
via: CR