I sometimes replace the last ES dose with the OJ/castor oil mixture. I find that this gives and extra flush similar but better in my opinion than the second AM dose of oo/gj.
The castor oil seems to stimulate more stones to release and it cleans everything out without taking the 4th dose of ES, which is too much alot of times.
Hope this helps. It is kind of my super flush. I have never read of anyone else doing it that way, but it works.