This is severance--moving part to a second volume--not "cutting". Organization of the second volume is ongoing--I took out two chapters near what is now the end of the proposed first volume, as well as the last 10 chapters, into the new second volume, and now need to write a good beginning for that one (massaging the two removed chapters should work) and then put back in the things dumped from the final 10 chapters to see if they still fit...obviously there's room in the second book for that re-expansion.
All of this is subject to editorial fiat, of course. But this way I can suggest an approach that I like and get it on the table first.