Plants can finish quicker; usually due to adverse conditions somewhere in the grow.
Your plant is weeks away from being ready. Lots of white pistils showing which indicates active calyx growth. A good tool is a loupe or digital microscope to determine the point of harvest.
This kind of magnification is what your need.
The amber you’re seeing now is on the sugar leaves, that’s normal
She is looking good for a first time grower nicely done, but she is not ready yet. She will stack up even more and you will be very happy to see it happen. She will be a frosty one that is for sure just keep her happy and when you start seeing about 50% of her pistil hairs die off and shrivel up.
Then you start looking at her trichs on the calyxs, and not the sugar leaves. This is when it becomes personal preference as to the ratios of clear, milky, and amber trichs.
Grow on and keep it up
Thanks for replies, decided to do a half strength feed this week and start my flush next week.
It appears as though u still have several weeks left. Not only can a plant finish sooner but they usually take longer.
Just my opinion but I wouldn’t start flushing for at least 2-3 weeks
Do as you like…learning to wait a little longer is hard when you first start, but you will be happier if you do.
I’ve been growing Girl Scout cookies for quite some time. You’ve got weeks to go. When all your pistols are red/brown and curling it’s just about ready. Good news is gsc really bulks up in the last 2-3 weeks. Be patient. You’re going to have some nice smoke 
Day 57 of flower, I know these arent the best magnified shots but any opinions when I should cut? Week 9 will be next monday. Also, is the flowering time the time when switched to a 12/12 schedule? Or is it when the plant first shows signs of flowers?
Day 1 of flower is the first day of actual flowering, not the day you switch to 12/12.
I don’t see much, if any, amber trichomes. They do look mostly cloudy.
Harvesting is a personal preference. Would you prefer a more energetic high that slowly drops off, or one that drops you into the couch like a sloth?
I personally believe the first day of flower is the flip just because its not arbitrary. You know the exact day. If you look at real flowers forming, who can see the first real flower? Its damn near microscopic. So its way too arbitrary on whether or not its real flowers or pre-flowers or whatever. I would just always add at least 2 weeks to the breeder’s specs, but be prepared to go 2 weeks beyond even that. So with a 9 week strain, just assume its 11 weeks, start at flip, but be as patient as you can.
Im growing GSC for the first time myself. Im doing some experimental growing techniques on it, but would you say they produce really large buds? I figure mine will flower for about 15 weeks due to my technique. How much would you get out of a plant say 2 feet in diameter? Were you doing autos or photos?