Check this diagram out:
View attachment 1152538
As the plant matures the new calyx (flower) will form making new hairs. As each calyx ripen the pistals in those individual calyx will shrivel and receed back. You're going to see a bunch of new calyx form with new hairs that shrivel, that's what makes up the bud. When it come time to harvest you're going to be looking for a number of things at once, not just the trich color like everyone says, there's more to it.
Here's the order the plant matures so you know what to expect-
1. calyx and pistals form
2. pistal hairs turn color and shrivel back to calyx wihich will have started swelling
3. calyx swell with resin
4. **Now is when to look for trich color**
The trichomes can start changing color from the time they develope so you can't rely on just that to judge harvest time.