is it harvest time?

To know for sure when to harvest there's only one way. Zoom at least 30x and check the thrichome heads. They have 3 stages. They go from transparent to milky and from milky to golden/brown. What you want is to cut when most of the thricomes are milky with a little bit of them passing to golden. In other subget you seem to have bleached flower on the top, probably light burn. Can also be bud rot, usually caused by excess humidity and poor airflow. I hope i could help you. Good grows

i think you should harvest now. It looks like you may have bud rot and the longer you leave the rot will continue to grow.

goddamn spam filter... mf'er. trichomes - need a 30x magnification pistils - preferably changed color and stating to coil up density - gently give 1 a squeeze and make sure it's got some density to it. don't do this except to make yourself feel better about the choice. less is more. more amber = more couchlock. you can take a cola off early and later than the bulk of your harvest. no harm will come in that time frame even if it is stressed out by it. you have light burn in this first 2 pictures. if the colas was much taller than the rest you can snap it at a point tha tbrings it in ine with the rest of the canopy. support it the first 24-48 hours and it'll be healed very fast. after that you may need to have a support holding it 'down', because it will try to go vertical again. The tip will bend to the light so you snap its stem 4-6" below canopy level in expectation, but the horizontal part will even try to bend upward, and you'll want to prevent that too. the tip going vertical is fine.