i'm no expert but from experience i have found that when alot of the fan leaves have turned yellow thats when the plant has drawn all of it's reserves from the fan leaves to feed the buds and thats about as far as it will go,i wouldn't chop yours just yet hopefully the buds will bulk up, might be worth posting a new thread to see what the experts say. i started to cover my plant about 3 months ago to force it into flower as it was getting to tall, i thought it was an indoor strain and was only going to be about 4FT tall ended up being just over 6ft, off to work now but i'll post you a pic of mine tonight.stay cool mate.