Grand Daddy Purple flowering discussion any advice welcome

I am growing in a Bc Northern Lights Producer. I just flipped over to flower on 2/2 five days ago. All the ones on the left /15 are GDP (grand daddy purple) the last row on right is Ace of Spades far right corner, far left corner middle is Cherry Bomb, and bottom right corner is OG Skywalker. For first two days I keep it pitch black to encourage more flower spots and to kick it into gear. They veg for three weeks prior. All Clones and advanced nutrients used. Here they are I'm open to any advice and questions.

Wow they exploded. They love the box. GDP is definitely gonna be one of my permit mother's. I'm also working on Chery Bomb from Bomb seeds is my favorite so far she's from seed. So far extremely great growth, better than the GDP very similar parents.
Cherry Bomb is the hard hitting, big yielding strain from Bomb Seeds. The result of crossing our monster yielding Big Bomb with a unique and fruity mother means growers can expect an explosion of flavour and maximum yields.

They are almost touching top. The cherry bomb is amazing, the stem are as big as thumb. Gdp is doing great too.

On the excellent phenotype of GDP that I ran, I reduced the nighttime temps to about 68 degrees, which really kicked in the bag-appealing purple color. As a result of doing this, a couple other strains turned a purple hue as well, with a couple not affected at all (no color change).

Wow nice. It's funny I'm growing purp and I think mine are nearly same age. My ladies stand 4' and looking a little light for 4.5 weeks in. On other strains I see bigger buds by this point. Is this normal for purp? Do mine look light to you?

OP: looking good, curious to know how the end results are.

Smokey Violet: those plants look like they having been spending all their energy reaching for the light, there is hardly any buds on them at all.