hey kuri, i have seen a question like yours posted in this forum somewhere in the post......the answer is yes.....you can do it.....you can increase speed but you will lose in both potency and yield....you can do it after week 6.....for one week lights down for 14 hours and finish a week earlier......instead after finishing week 7 give them 2 days of complete darkness and then harvest them......in this way you will have both potency and yield!