Dr. Google and Co., has so many conflicting opinions on what time of day to use opks! I've seen FMU because that's when most concentrated, second morning urine, afternoon wee, right at midnight (ok I haven't seen that one yet ) But, honestly what time of day do you use yours? Last month I used clearblue digital advanced, which called for FMU. This time I acvidentally purchased clearblue EASY digital opk, which just says take after a 4hr hold on the instructions. I'm on cd 5, and got my positive smiley cd 9 last month (first month ttc). So, I plan to start them soon. I originally thought I would use them 2x a day,but I've already spent $38 on this box of 20! No wondfos, as I can't interpret lines wondering is it or is it not lol.