You can post again in 12 weeks and there will be at least a couple of people replying "give it two more weeks".
Follow the rough guidelines, e.g. what
@VincenzioVonHook said above, cut a few flowers successively while the plant is still growing, then you can assess the quality later. Probably you will find that a few days do not make a lot of difference to the smoke.
This issue of "perfect harvest time" is vastly overblown, obviously harvesting way too early will cost yield, but past a certain point it really does not make a difference any longer.