Calender changing?

Ashley
Question. Has anyone seen that their calendar changes if you tell glow your period is late?? 
I'm 7 days late and have been logging that. When I went to September calendar to maybe get an idea of when I would have conceived and it changed my fertile week (green). I specifically know the dates from last month (only cause I was discouraged cause hubby was gonna be gone when the hugest day was). Is the change because I'm tellin it AF is late so far??