So Arimidex at .25mg 2x a week did absolutely nothing to your E2 levels. Maybe instead of bumping it up to .5mg 2x a week you could try .25mg EOD. Maybe only taking it 2x a week is causing a spike/rebound effect, cause it's half-life is 36 hours.

I'm battling high E2 problems currently. Mine tested at 71 in a range of 0-54 last time and my doc wanted to bump up my Arimidex dose to .5mg 5x a week. Just wanted to give you another example.