NL Auto Day 56 — after major nutrient imbalance: I don’t know how to rehabilitate or determine when ready to flush and harvest... Suggestions for a n00

It is pretty normal for the leaves at late flowering to go yellow, so nothing really to worry about. The close up picture looks like that plant is close to harvest, don't worry about "amber trichome percentages" some plants will never have amber trichomes and some plants will have amber trichomes very early on, depending entirely on genetics. I am a bit worried about the first and third pictures, there seems, what looks like to me, a fungal problem starting to raise its ugly head, with the black blotches being the tell tale sign. I would be stopping all nutrients, letting things dry out a bit and only giving water for the next week or so and be considering harvest soon rather than later. You don't want all your hard work and big chunky blooms going mouldy. Perhaps if you haven't fed them for a few days, harvest could be brought forward a few days. Remember, you will never stop learning when growing this wonderful plant and as a self described "newbie", should be proud of your results. Think how much you learned this time and how you can apply that knowledge into your next grow. I have been at it for 35+ years and am still learning new things every season. Congratulations on your adventure into the wonderful world of gardening for pleasure! Hope this helps... Organoman.