Logging issue

I'm on my first full cycle with Glow. It predicted the start of AF on Saturday (obvs. based on very little data).  I assumed that I would actually be able to log the real the data, and Glow would adjust, update and be a better predictor over time. However, AF arrived this morning, rather than yesterday. I logged it, but Glow is still insisting that yesterday was my first cycle day. Does the program really not update to reflect actual logged facts?  If that's the case, then it's really not going to be very useful to me.  Has anybody found a way around this?