Interesting document about differences between salivary and blood serum tests. I recently decided to test my saliva free E2 levels and my level was extremely high. I am using estradiol spray Lenzetto (Evamist). This document explains why the result was so high and much more facts about sex. hormones, transdermal application etc...
https://www.docdroid.net/vJYncsP/townsend20letter1.pdf.html
I worry more about my feminization, breast growth, well-being than levels. If things are going well, why fret about levels?