There are very few photoperiod plants that would be ready mid September in my hemisphere. I'm in the USA where regardless of where you're at, photos don't start flowering until at the very earliest, early August. Even fast flowering F1's don't move that time window by much ... that means at most a cultivar has been flowering for 6 weeks in this neck of the woods. I'm in Michigan where that means 4 weeks of flower. Almost nothing finishes flowering in 4 weeks and few finish in 6. Most outdoor grows will mature during the month of October. There are a few outliers finishing both slightly sooner and some later ... What this means is almost every question regarding an outdoor grown photo period in N. America being done in the middle of September is premature. Almost none will be ready at this time.
What I see suggests you'll be harvesting around the middle of October. As long as your weather holds out and your plants are healthy, don't try to harvest sooner. The extra time means extra weight and potency.