Canon is expected to announce quite a few new lenses in 2017. Among them are the EF 200-600mm f/4.5-5.6 Super Zoom, EF 600mm f/4 DO BR and EF 70-200mm f/2.8L IS III.
Now you can add another possibility to the list - EF 85mm f/1.4L. Although this new glass is slightly 'slower' than the current EF 85mm f/.12L II lens, if I were a betting person, I'd say this will be a replacement for the current model. The present EF 85mm Series II lens was announced back in 2006.
In addition, Canon has another Super Telephoto lens with built-in extenders patented - EF 400mm f/2.8L IS 1.4x + 1.7x Extender USM. You can see how Canon manufactures its EF and Super Telephoto lenses by clicking on their video links.
Of course, with estimated product delivery timetables, nothing is set in stone. Delays and changes in production plans may alter the announcement dates but it's safe to say, 2017 will be an exciting year for new lens introduction. You can see my equipment bag and works on MichaelDanielHo.com