According to CanonRumors, the telephoto prime lens EF 135mm f/2L II USM lens prototype currently exists, this lens will replace the EF 135mm f/2L USM lens which is announced many years ago.
Canon may also announce new version of 50mm and 85mm L lenses in 2017, and this 135mm L lens hasn’t been testing by photographers. So announcement date of the EF 135mm f/2L II USM lens could be in 2017 or 2018.
via: CR
See also: 2016 Canon Black Friday & Cyber Monday Deals