A good source has chimed in on the possibility of a Canon EOS R body with an APS-C sensor.
In a recent interview, a Canon executive made a comment about the EOS M and EOS R systems, saying (google translated) “Since EOS R is a full-size system, it can not be downsized to EOS M size. EOS M has a role/existence value as an APS-C system.”
A few sites took that to mean that there would be no APS-C sensor equipped EOS R body. We took it to mean that they cannot shrink the RF mount and the ergonomics needed for a “prosumer/professional” camera to the EOS M size of a camera and that a compact APS-C system like the EOS M would continue to exist for the foreseeable future.
Back to the source. We've been told numerous times in the past and again this week that at least one APS-C equipped camera is currently being developed and tested.
Why do we believe this? The EOS 7D series of cameras. If EOS R and the RF mount as the future for Canon, which I think most people they are. There is no way that the hugely popular EOS 7D series of cameras is going to be cancelled or just remain a DSLR. There will have to be some kind of EOS R replacement for it. The feature set of the line, mixed with its affordable cost make it a camera that must exist in the Canon lineup.
When could an APS-C EOS R body arrive? I would think after the “professional/sports/wildlife” EOS R body. This point is just a prediction.
Interestingly, there is absolutely no reliable information out there about a Canon EOS 7D Mark III camera. We haven't received a confirmation that such a camera is coming as of yet. That could all change, and we think the first half of 2019 is likely when we'll hear or see something about the line.