Is there nothing in the new catalogue offering some sort of cross reference to the old groupings? That would be quite strange if they just changed it all up and offered collectors no guide.....
Here's B+W's response received today:
You are right insofar as virtually all of the catalogue listings have been revised or rewritten, including in many cases the lists of shades. Most of these have been prepared by experts in their field. Unfortunately, there is no listing to correlate the new listings with the old ones, although in most cases they can be matched. In some cases additional new shades are listed, and a very few have been omitted. Good luck with collecting.
So they don't have a cross-reference of old to new catalogue numbers. I am going back to them to see if they have an old to new COLOR cross-reference.