The answer to your question is, fast till completion, till you feel true hunger. Most of us focus on what is right and wrong, what ifs and worrying about the results instead of just doing it.
Both your plans will help you. One cannot predict which plan will remove your cancer. Your past fasts are also the contributors to your healing.
I do want to add to your plan of 8-10-8. You should include Budwig protocol during refeeding period.
I am right now doing Dr. Shulze's 5 day kidney cleanse and I am feeling so good and happy doing it. Perhaps you can also benefit from a kidney cleanse. I must say that Dr. Shulze's instructions do not give you a detailed plan for the day so you have to plan your day.