Flowering/Harvest time?

What does it mean when the tendrils that are coming out of the bud start to turn brown?

you mean the pistils? The white hairs start to turn brown during flowering. This is normal and a sign that the buds are maturing. When the hairs are mostly brownish/red and start to tuck into the bud, then usually it is time to harvest.

Tendrils YOU HAVE GROWN A MUTANT!

It's a sign of maturity (bud wise).
Harvest when 40% - 80% have turned brown / orange-ish.

You should also check the trichomes (if you have a microscope).
The trichomes will start out clear then turn milky and finally brownish.