Should I extend?

You should be harvesting soon, real soon, any much longer and you are going to lose lots of THC as it breaks down into CBD, giving you a sleepy effect rather than maximum high.

They all seem clear to me. Try adding molasses to increase quality, and as flush agent. Molasses let the leaves release the final accumulated nutrients to the flower and increase terpene/oil production.

Your trichomes are still clear so MY opinion is you've still got a couple of weeks to go. If you want to "slow flush" just stop giving her nutes and she'll start to fade in about 2 weeks and the trichs will cloud up and then turn amber... and you'll be in trim jail by the look of what you have to harvest! Good luck!

High ItsCannaDog, The best thing you can do is buy a x60 pocket microscope and start flushing when the trichomes start to turn cloudy and some still clear. Then you should be ready for harvest when there are around 10% amber trichomes. But my guess when I look at your plants is that you can start flushing soon. Happy Harvest! 😋