Unless it's a seed from an auto--which it might since it's bag seed and autos can and do hermie a bit more than photos. If it's an auto, which I'd think it is based on you saying it started flowering in mid July, I'd say you should be good to chop by third week or maybe last week of August.
Still, it totally depends on the genetics, but I'm definitely leaning toward it being an auto if it started flowering with this much natural light every day. Maybe it's an Iranian that's really eager to produce.
Start here: How tall is it?