It's clear that Canon intends to bring more bodies into their EOS R mirrorless line. Now, it looks as if an ultra-high-resolution camera may be part of what's in store.
Canon Rumors is reporting that an EOS R body with just over 75 megapixels is in development. While Canon has the 5DS R, it wasn't until the 80D and subsequent cameras that we saw a marked shift in sensor quality and dynamic range from the company, so it would be quite interesting to see how a high-resolution sensor made with their newer techniques performs.
Looking at the current lens lineup, I can easily believe Canon is planning such a move. The company seems to be aiming for pretty high standards with their RF lenses, and as such, it would be a reasonable move to see them release a body that could take advantage of those optics and give them major bragging rights in the full frame arena. As discussed before, Canon seems to be diverting some additional attention away from DSLR development toward mirrorless development instead, and it's likely that that would specifically be for the replacement body for the 5DS R. One thing is for certain: 2019 is going to be a very exciting year for mirrorless shooters. Head over to Canon Rumors for more on the story.