My understanding is that would be R8RS, and would be a continuation of R6RS. They seem to be doing the tick tock sort of model of alternating focuses for "releases".
Thanks - in fact bgruber's video link above [1] about R7RS-small also includes a section about R7RS-large too. I hadn't seen the video when I asked my question.
Basically another working group will work out the details at a later date and it will be much larger - about 80 packages and probably bigger than Common Lisp according to the video.
