Can't decide when to harvest/start-flushing; cloudy trichomes, but 90% white pistils

Hey guys, I have 1 BIG plant that is really close to harvesting time. Its in soil and I'm using fox farms nutes. Today is day 55 of flowering. I've looked at my trichomes with a 100x microscope and the trichomes really vary from bud to bud. For example, my main cola, and most of the other colas (the higher branches) that are DIRECTLY under my hps aren't looking quite done yet. Almost all of the hairs are still white and the trichomes are about half cloudy and half clear AND the buds are still gaining girth. The very top of my main cola is as big around as a coke can and still stretching. The pistils definitely aren't receding yet.. in fact, I think new ones have been growing. The main cola is not where you would think to look in the pictures because I broke the stem at a 90 degree angle 2 different times (because of growth height restrictions) so it is in kind of an "L" shape. If you watch the video you'll see what I'm talking about. On the other hand, some of my other colas that aren't directly under the light (my lower limbs) are looking RIPE and completely READY TO GO (see pics.) Another thing that is starting to happen now is the fan leaves around my biggest colas (top branches right directly under light) are starting to turn yellow... some are even dying off. Its concerning because those are the buds that still have almost 100% white pistils. Yet, my lower branches have really dark green healthy fan leaves. The ones that are looking ready to go have about 40% brown hairs and mostly cloudy trichomes (a few amber.) I've been on egg shells about when to start flushing, because I don't want to wait too long, but my biggest main buds don't look ready (almost no brown hairs) and I don't want to starve them of nutes. Every time I feed it nutes, i see these new shoots of buds swelling out... but I know I need to start flushing soon. I ordered some Clearex via emergency overnight shipping to help me flush faster if I need to. Being that it is bagseed, I don't know what strain it is (and how much sativa or indica,) but it was a very bushy plant so I'm thinking mostly Indica. I'll post a whole lot of pics so hopefully you can kinda see whats going on. I'll post a video as well.

Quick Update: I got the clearex in, and flushed with about 6 gallons of ph adjusted water (with clearex.) After my runoff was clear, I mixed up half-strength nutes and fed her again. I think its too late for most of the yellow leaves, and I'm almost positive now (after reading for hours about other people with similar issues) that that is due to the plant saying "hey I'm finishing flowering," and not due to nutrient deficiency. No idea why they don't look ready then... One thing I have noticed is that my lower branches that are getting light mostly from 2 cfls I have hanging from the side are getting some brown pistils, and even some of my middle growth that is being hit by the HPS. But my big colas that are 4 inches from the glass of my hps (sealed and air cooled with a 450cfm fan, i can touch the glass very comfortable, not hot) are the ones getting yellow leaves and all white pistils... Too much light?? I don't know... Thanks for the help guys. Looks like If I do a proper 2 week flush, I am going to be almost 10 weeks into flowering before harvest.






























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Link to video: VID_20120611_215725[1].mp4 - YouTube

Looks good, but I'd give it atleast 2 weeks. My blue dream when I harvest still has about 15-20% white hairs. After about 3 days of hang drying I notice that my hairs will become darker like the rest of the nugs. Also IMO i like to keep my plants as healthy as possible until flush. Some people tend to start to drop the nitro intake which will cause yellowing in the leaves quicker. And when you do that IMO it stresses out the plant because it has to focus more energy to kill off the dying leaves or to try n re coop the dying leaves. Either way taking up pressicous nutes from the bud to heal the wounds. Just my 2 cents.