is my Glow App calendar/AF/ovulation predictor changing on me?

Paige
Has anyone else had that happen?!? 
Yesterday, it was predicting AF to arrive on the 22nd, and showed this past Friday as my most fortune day. Today was supposed to be the last day of my ovulation window. 
Now, it's showing AF is scheduled to arrive on the 27th, and TOMORROW is my most fertile day...I'm so confused. Has this happened to anyone else?!? Did I miss something?