Clearblue advanced OPK

Charlotte

Hi ladies, this is my 2nd month using clearblue advanced OPKs. Last month I only had 1 day of flashing smileys then my peak smiley on the day before my predicted ovulation date.

This month Glow predicts I will ovulate next Tuesday 30th April, this morning I tested and got my first flashing smiley. Could it be I may ovulate earlier than predicted? Or may my fertile window be longer this time around?

Thanks in advance!