Not every plant is going to fade, even if it's nice to see in a soil grow. I've had very nice hydro plants that were green through harvest even though I let them go nice and long at the end. If the trichomes and overall pistil/bud structure are indicating it's time to harvest that is the most important thing. My first impression is that they could go a little longer, but trichomes would tell you more than can from the photo. You may already be scouting them, but if not look for a portion of amber directly on buds, ignoring the most freshly stacked calyxes. Happy growing! 🌱👍