I know that a lot of American IVF clinics put their patients on BCP to "synch" their cycles. I've never heard of using the pill in the same cycle as clomid (or other fertility meds) though. I thought the way it works is that you take the pill for however many days you need to adjust your timing, then stop, get the withdrawal bleed, which you treat as CD1 and then start your treatment cycle as normal, but with CD1 on a different day to what your natural cycle would have produced.