Trichomes going amber on a plant on day 50

[MarvoHarx]

Pretty sure 3/4 of my plants are in nutrient lock out, been giving them pure water the last few times to try to flush them out. The lower leaves have gone back to a healthy green. My question though, when I examine the trichomes on one of them, the majority appear to have turned amber already. I’m only on day 50 of flowering. The other three plants are still in the milky/clear stages. Should I wait to harvest? I don’t have close up pics of the trichomes but have included a pic that shows the buds and terrible upper leaf health lol any tips would be appreciated.

 

[LoveGrowingIt]

I'd probably harvest it if the trichomes are amber. Not sure what happened to it.