plant spotting please HELP

I have a little problem im not sure if its even worth correcting though. i am two weeks away from harvest , {so far} just the top section of sun leaves are showing heavy amounts of brown spotting. never had any deficencys or nutient problems or bugs, but the newest addition to these particular set of girls { two weeks till harvest already} Is that I completely stopped nutrients and added "humbolts own GRAVITY" a flower hardener and finisher ,and a touch of molasses, as per the GRAVITY product suggested. Im wondering if one of the three changes had any play in this condition. knowing that nutients are supposed to be withheld in the last weeks of harvest. Should I flush?? and or reapply nutients if a nutrient problem??