Tha Auto glueberry O.G.’s

This is week 11 since germ in two days, I was hoping someone can tell me how long left and when to start flush probably 30/70 orange to white pistil ratio, I’m also seeing some yellowing and some tips of the leaves going purple. I think theirs two, three weeks left but id love to hear someone’s two cents on it all cause this is my second grow and first autoflower, it was estimated 10 week from seed but I know that’s a rough estimate.