New Growth on Mature Buds, Just Before Harvest

Now at the end of my best grow ever, my mature buds are suddenly sprouting new growth. I checked the old trichomes under a microscope over the weekend, and I have about 70% cloudy, 30% clear, and just a few ambers. I was preparing to harvest this weekend, but now I'm not sure what to do. I read on some other threads that plants can change growth patterns based on environmental changes.

I've only changed a few things recently. Since the days are getting warmer, I ran a vent under the house so the hot flowering room can get cool outside air at night (daytime for the plants). This brought the canopy temp down from 88F to about 78F. I also started a second batch of plants in the same room under a new 600W HPS, which is now providing a little side lighting to the mature plants. I stopped adding the regular nutrient regimen, and switched to some dilute finishing nutes on May 4th. I included a pic, but you can't really see the new growth very well.

Girl Scout Cookies in soil with organic nutrients
12/12 cycle under 1000W HPS
Pitch black during dark hours

Hey dude what your experiencing is a normal phase. Most plants keep putting out more and more flower and fruits thought out the season and weed is no different.
I think I've heard this stage called crowning before not sure.
When my plants hit this stage i usually let em go a week or too longer until the buds look like they're reading to smoke off the plant.
Trichomes at this stage have shit loads of Amber but beware of trichs because like the flowers they come in surges.

I was going to chop once and did a last minute trichs check and they'd all changed from cloudy/amber to clear.

I now find the best method to tell if they're ready is just to look at them, like i said, if they look ready to smoke, they are.

lots of strains do that, especially sativas, some NEVER stop flowering, but peak potency can only be determined by close observation and a good eye. Don't worry about it.
that being said, from the pic (hard to tell obviously) it looks like it could go a bit longer to me.

Thanks for the info Vegan. Now that I know the condition is very common and that it's called crowning/foxtailing, I was able to do a little research.

The buds actually look ready to smoke, but I harvested a little too early with the last batch, and I don't want to make that mistake again, so I'm trusting the trichomes this time.

It's been 3 days since the last inspection, so I'll take another sample today.