I've always ovulated on CD13 but just had a tubal reversal on September 24, which can alter your cycles. I bought some IC OPKs to use but I keep finding conflicting info on using them. Am I supposed to pee in the cup and dip it once a day or twice a day? Any specific time of day that is best? What CDs should I start using them in case I don't O on CD13? TIA!!!