Monthly calendar

Amie • 👫🏻 2011. 💍 2011. 🐶 2013. 👰🏻🤵🏻 2013. 🏡 2015.
So on a normal cycle I should have excepted AF yesterday. Glow shows AF coming next week though... Could this be because last month AF was late so it's going off by what happened last month?