So after my last period glow predicted my next period on the 27th Jan, this month I used ovulation tests and got a positive two days after glow predicted my most fertile day, and now it’s changed my period to the 29th, now normally glow is right with my periods and it comes exactly when glow says it will but one month it will be 23days between periods some months 24-25 days between yet glow still always gets it bang on, but now it’s changed my dates shall I go with the first date of the 27th or the 29th???