We sent this information out last week in our newsletter and we haven't received any further clarity about the Canon EOS 7D Mark III.
There has been a lot of unfocused chatter about an EOS 7D Mark III recently, and in my experience, that's not a good thing.
Our best source is telling us that they haven't heard anything about an update to Canon's flagship APS-C camera. That doesn't mean one isn't coming in 2018, but the earliest it would be coming is Q4 of 2018, and not the rumored first half of 2018 that we've been told previously and others keep reporting.
There'a always a possibility that Canon is changing the way they launch popular flagship products to try and make it harder for sites like this to leak information. Although I don't think that highly of myself or that I would wield that much influence over Canon Inc.
We'll keep you updated and we will resist posting about the EOS 7D Mark III until we get a better feeling about what is true and what isn't.