According to a report from CanonWatch (via Mirrorless Rumors), it seems that Canon might have a higher-resolution version of the EOS R that they could announce at Photokina 2019 which is scheduled to take place in May 2019. Details and specs of the alleged camera are sparse at the moment so it’s really anyone’s guess as to what Canon could announce.
That being said, this doesn’t really come as a surprise because last month, a rumor suggested that Canon might announce two more EOS R bodies in 2019 so an announcement at Photokina 2019 doesn’t really seem like much of a stretch. Canon’s approach seems to be a bit different from companies such as Nikon, who have also gotten more “serious” about their mirrorless efforts.
Unlike Canon who chose to announce one model, Nikon actually announced two models in the Z6 and Z7, giving users more options out of the gate. In any case take this with a grain of salt for now, but if you are still undecided on the EOS R, maybe waiting until next year to see what else Canon might have might not be such a bad idea.