I have been told that the new features firmware for the Canon EOS R5, Canon EOS R6 and Canon EOS-1D X Mark III is “done” and will be released in the next couple of weeks.
The EOS R5, EOS R6 and EOS-1D X Mark III will all get C-Log 3 and new compression for 4K video.
The EOS R5 and EOS-1D X Mark III will get a Cinema RAW Light option.
The addition of 1080p @120fps will definitely be coming to the EOS R5 as well.
As always with any firmware, a bug could be found that may delay things, but by the sounds of it, the firmware is going out to testers and reviewers relatively soon if it hasn’t gone out already.