ff is expecting my o to be on the 2nd of february. when would you start taking opks knowing that this is the first "real" months after stopping bcp?

I temped for 2 months before I started using OPKs so I knew for sure when my range was likely to be.  If you are set on using them this month I would start 3-5 days before your expected O date as you get the LH surge which is detected by OPKs before you actually O.  I know 5 days sounds like a lot, but I O anywhere between CD13 and CD16 and FF is just guessing on your O date so you don't know for sure....HTH!

My OPK's say to start on CD 5 and to test twice a day.