Trichomes CBD 85%-15%-0%?

Looking good! I'd give it another few weeks. Looks like there's quite a few clears on the calyx' so your intuition is close in my books, but my preference is having at least 10-15% amber :) The calyx' trichomes are starting to cloud-up, so they'll still need to cloud the entire heads before getting white and milky. If I've got this right, the reason their pigment will turn orange is they're transitioning from THC to CBN. So if you're wanting more CBN in your CBD strain, might be worth pushing it til there substantially more amber e.g. 20% I'd push it as long as possible so the calyx' can swell up substantially. Personally, I also ensure there aren't many white pistils (strain dependant) and instead, pistils are orange and shaky. This is often weeks longer than marketed 'finish' time. Keep on watering and keeping her going and enjoy your harvest!