Test Cypionate half-life

Can anyone tell me how long it will take for my blood plasma levels to reach an certain level?
Specifically, I am currently using 750mgs of Test Cypionate weekly. I need to get a total testosterone blood test done in a month or so and I wanted to be certian my blood levels were in an acceptable range. My doctor perscibed 200 mgs, every two weeks, but I really wanted him to either up the dosage, or the frequency, or both, hence I want my plasma levels to be low when I'm tested, defintley not high!
Thanks!

I thought that it was three weeks, but don't quote me.