According to latest rumors, Canon is rumored to announce a new RF mount telephoto zoom lens RF 70-135mm f/2L USM Lens at the end of this year. This lens has been testing by a very small group of photographers and videographers.
Since upcoming Canon EOS R5 and Canon EOS R6 will have IBIS, so it make sense that RF 70-135mm f/2L USM lens will not have IS and to save the weight.
via: CR