I don't know how much you can trust the 12/12 light cycle. I have a feeling that plants start flowering before that. I live in Lausanne, Switzerland and 12/12 starts here on the 25th of september. However my plant has been flowering for 5 weeks already and will probably be ready for harvest before the 12/12 even starts, which is still 4 weeks away from now. I'm a first time grower so I don't want to make any blunt statements but maybe a 13/11 is enough for flowering. I think dropping temperatures play a roll too. Plant looks good tho! That's what mine looked like at the end of the first week of flowering. Cheers!

Btw! on www.timeanddate.com you can look up when the sun rises and sets for every month of the next 20 years or so!