We're told that Canon plans to announced the successor to the EOS 7D Mark II some time in the first half of 2018. The CP+ trade show in February is a logical possibility, although not guaranteed as I'd expect the EOS 90D to come for that show.
The EOS 7D Mark II was announced ahead of Photokina in 2014, which is where we expected a follow-up to be announced in 2018.
While we have no specifications, we are told that the EOS 7D Mark III will come with a few more video bells and whistles, like 4K recording, which at the time of writing this would be the first APS-C Canon camera to have this feature.
My gut says we'll see an EOS 90D announced before the EOS 7D Mark III, so the “first half of 2018” could mean late Q2.
More to come…