SOLVED: Perhaps this will help others. I use Adobe Acrobat DC.
When that program is open before I select print, I run into the problem described below. However, if Adobe Acrobat DC is closed BEFORE I hit Print to PDF then all work brilliantly. An annoying little bug, but one I can live with now that I see the conflict.
I've recently run into a problem that I haven't experienced before.
When doing a multi-page print (PDF) of my route ( https://www.plotaroute.com/route/834145 ) the elevations are replaced with a "buffering" type icon, and directions are non-existent.