I'm growing the same strain. I'm a few weeks behind you. My girl has just started flowering. Honestly I was expecting this plant to get much larger. She is just a toy!
Try to look at the trichomes to determine when to harvest. You'll need a jeweler's loupe or some way to magnify the buds. Look for the bulbs to be milky to amber for harvesting. Make sure you are looking at the buds and not the sugar leaves.
You can begin flushing when you feel that you are about 2 weeks from harvest. I usually will start flushing as soon as I see an amber trichome, or when I lose patience. However, I always wait until all of the trichomes I look at are milky.
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