Thank you Camille.
I appreciated that website with Kathleen's count of the caffeine amount in various beverages.
Today , first came two caffeinated green teas , then at a coffee hour I had decaf. By mid afternoon I felt dulled and sleepy ( very unusual for me ) I allowed myself half a regular Earl Grey for my slow countdown approach.
I drank decaf after 3 p.m anyway so am on the home stretch.
This encourages me to drink far more water and that can only be good. It may not be as difficult as I imagined.