The solution is to use `make autoloads'. I suppose that should have been obvious to me at the beginning. After git pull (`+' in vc-dir) the working recipe is:
1. rm *.elc 2. Update in org-mode buffer using C-c C-x ! 3. make clean 4. make autoloads 5. Check update org-mode via C-c C-x! 6. make 7. Check update org-mode again via C-c C-x! Some of these steps might not be necessary. I will experiment. Thank you all again for your help. Best wishes, Colin.
