The 6wk blood req is generated 36 days after your doctors visit and initial RX is written. This is obviously early than 6wks but it's sent then to make sure you have it on time. It's called the 6wk blood test but there's nothing specifically special about exactly 6wks. It's recommended that you get it done sometime between week 5-7. So that give the individual plenty of time. The day your blood req is uploaded, you should receive an automatic email notification, and a phone call.

The 6wk blood test includes Free and Total testosterone, Estradiol, and both the CBC and CHMP 14 panel.
The 6month blood test includes the same along with a Lipid and PSA panel.