I know this post is a couple years old but for those looking for a more recent response, like I desperately was, I figured I'd respond.
This is the first time using the CBFM. Last cycle I used FLO. This cycle decided to use FLO and CBFM. I had 7 high fertility days CD6-CD12, and even tested twice the last 3 days, and still got the flashy smiley face. I was about to give up thinking I missed the peak or just wasn't ovulating this cycle OR the kit just wasn't working for me. Later the night of CD12, the 7th high fertility day, after the 2nd test, I got the "egg white" cervical mucus! I thought well this is a sign I am or am about to ovulate, whether the test says it or not. The next morning (today) I got the static smiley face! I really didn't think I would ever get it. It is really empowering to know what to look for and then get reinforcement of it with the test!
Now is the waiting game. My husband and I are so ready for our Rainbow baby. Hopefully this is the month. 