Elbows are starting to ache, last time that happened my estrogen was in the low teens.
I'm a bit unorthodox. I like to do 1.25mg daily for a couple weeks which usually plummets my estrogen. Then I drop the letro and either run exemestane or no AI at all. Once I feel estrogen has risen again usually after a month or so, I do it all over again. So far I'm liking this approach.