Why only run anastrozole once you begin anavar? The anarvar is not the reason you're using an ai.
Why not run 100/100/50/50 clomid to be safe? PCT is as important if not more important than the gear itself(basically im saying why skimp on the portion of the cycle that helps you keep what you gain. See how to standard pct works for you and you can experiment later on when you know what to expect.
May want to look into estrogen rebound. Thats why some people run clomid/aromasin and clomid/nolva as pct. Cant say 100% if it is present with anastrozole and I dont feel like researching it again haha.