Is there a reason you wait a week after Test to start anastrozole? Is is necessary to stagger the timing with a longer ester? I would thing managing your E levels from the beginning would be more in keeping with the 'preventative not reactionary' philosophy of AI use on cycle. Also it does take a few days to get an even and active level of anastrozole in your system. Though I'm not sure if it makes a huge difference in a clinical setting, one way or the other.
And along the same lines, since asastrozole binds reversibly, you may want to carry it all the way through week 12 backed up to your PCT to avoid any E rebound during those two weeks of waiting while you still have long Ester test in your system.