News about the long rumored supertelephoto zoom from Canon has gone quiet over the last 6 months or so, but we're now being told the lens is coming in 2018, though the exact time of the announcement is currently unknown. Though the source did say it would not be coming for CES or CP+ in the first quarter of 2018.
As you know, there has been patents for a 200-600mm f/4.5-5.6 IS optical formula in the past. The source did say any super telephoto zoom such as this will not be an L lens, as to not “step on” the EF 100-400mm f/4.5-5.6L IS II and to keep the retail price in line with the consumers that buy these type of lenses. Likely, it's also to remain price competitive with both Sigma and Tamron.
We still do not know which two lenses appeared for certification recently, but we hope to know more soon.