Silly question--OPKs

Helen 🦕😄
I know that an OPK is negative if the test line is more faint than the control line and that they must be the same color. When the line is present but faint does it have any indication on when the surge will be? Like, is there always a little LH or is a faint line saying, it's a week, five days, ten days off? 
Thank you all!