The perfect state of trichome maturity is a personal matter, like an ice cream flavor. I may prefer vanilla, and you chocolate. And if you have no personal frame of reference for what you like yet, then you must rely upon the advice of others as a starting point.
And it can be strain dependent.
So you have selected all milky as your target, and you should harvest.
Or as Painted suggested, take some and leave others.
I’ve harvested at every stage, and have learned I like a fairly mature stone in which about half the trichs are amber.
Enjoy growing and your harvest!
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