Even though the pistils are still light in color? Would waiting a few more days have any ill effect? I'm trying to get a friend to come to my house and look at it up close.
I had something similar happen to a couple of my plants. The same curling leaves which were turning the same color. But it did not happen to my plants as fast as it is happening to yours. After the fan leaves shriveled up I noticed that the buds were drying out. Not all of them, it would start with the lower ones on a branch and then move up to the top of the stem, one bud after another.
The first time was on two plants, both clones, and I had planned the harvest at 8 weeks. There were very few buds left my then that looked good. Most of them were dry, crunched when squeezed, had no aroma and were not sticky. It even looked like the trichomes had fallen off. If I remember right, what happened was I ended up with a little less than half of what I should have.
Then two other clones started to show the same signs. Rather than wait till the scheduled harvest I cut them down shortly after I saw the problem. The harvest was close to what I expected and just a few buds were dry, crunchy, brown with no aroma. This is why I am thinking that you should be ready to harvest the plant soon. Keep an eye on the plant.
Since then, the soil has been used again to grow clones from the same mother plant, from other mother plants, clones of the same strain and clones from other strains. All plants had been watered and fertilized on the same schedule.The problem has not come back. Plants that were touching these plants did not develop the problem.
You have gotten a good plant. Now is a good time to prepare for the next attempt. Keep track of what you do for soil, for watering, for fertilizing and lights. What many members here recommend is starting a journal which helps document what and when something is being done. Keep basic notes and don't loose them.
I am still interested in whatever you decide to do with the current plant. Maybe a photograph every now and then and mention what you see because we often see something that does not show up in a photo.