they either fibbed, or you got an unusual phenotype when it comes to bloom period.. They may not have made it as consistent as they say.
Depriving a plant of light does nothing good. Don't do that. If doing somethign like this "seems" to improve canopy, it is likely due to avoiding hot/inefficient lights evaporating off trichomes than any benefit the dark had.
Stigma (white hair) color is a horribel thing to go by. I've had several that are still quite a bit white at harvest when trichomes are ready.
You need a 30-60x magnification. Otherwise it is more of a guess -- always a guess to some extent.
give it 10weeks.. re-assess along the way, if needed..That looks immature still.