Periods

So I have been taking the pill since the end of May. I had two periods the month of June and then in July my period was more of a pink discharge then a period. Started exactly when my app said it would. All of those times though my period has been in the middle of the pack, not during my placebo pills. My second pack I did have very very minimal brown spotting when I wiped during my placebo pills. I’m following an app and it says I should get my period August 8 which is directly in the middle of my pack. Should I expect a period then? How long does it take for your period to line up with placebo pills. This is my third pack