Yeah, they have a few more weeks to go. You might be happy with the buzz after two more weeks of growth, so you could clip a bud and give it a try. Then you could let it mature for another week and try it again, and so on and so forth. Honestly though, you have at least another 3 weeks. I'm guessing the pistils will start turning in 10-14 days, and continue to do so for the next 10-14 days. After you have 50+% brown pistils, the buds don't put on much more weight after that, so you can chop them whenever you're happy with the buzz, and not lose any yield. Then when it comes time for the next harvest, you'll know when you want to harvest them, remembering from the last grow. Alot of it is preference, as some people like a more 'head high'(earlier harvest) and some like more of a 'couchlock buzz' associated with a later harvest, when the trichs start turning an amber color. You're best bet is to buy a cheap microscope(100X power, minimum, and are $15 on Ebay) while you're waiting, and monitor the trichs as they mature.
I think you should not stress about what they say about the period of growth, just follow what your plant tells you and be patient you've gotten this far haven't you, and she will be like any other gorgeous Woman well worth the wait. Hope this helps
