Fixing Nitrogen Deficiency Going Into Flowering?

Hello there friends,

First time grower here, and I have a few massive blue dream "bushes". Both of these ladies happily grew over 6' tall with many branches even after FIM'ing, up until a few weeks ago. Now they are both displaying what I think to be a nitrogen deficiency. They also appear to be beginning to flower, with hairs developing and trichomes sprinkling the tops of the colas.

All of the colas have these funky lime green leaves, with dark veins at the center. They also feel kind of...odd...to the touch, compared to the darker green leaves. I have been diligent about PH'ing the water to ~6.0, but am growing outside and have received rain showers here and there.
After doing a bit of research, I went and bought an NPK testing kit to confirm my suspicions. The two tests that I did showed the P and K coming up as abundant, while the N showed that it is depleted.

I suppose that leaves me with two pressing questions:
Does this indeed look like a nitrogen deficiency?
If it is a nitrogen deficiency, should I try and correct the problem while my plants have begun to flower?

I read that nitrogen can hurt the plants as they are flowering, and am hesitant to make my problems worse by adding a lot to the soil. So far I have used Fox Farms trio and CalMag at half strength every other watering, and they seemed to enjoy it.

Any help is greatly appreciated!

Nitrogen doesn't hurt the plant during flower. It makes the buds more leafy. A decrease in nitrogen is fine, but you don't want to cut too much.

That's not symptomatic of a Nitrogen deficiency.
Nitrogen is mobile and any lack thereof will show on older leaves first, not new growth.

I've found the plant's needs for nitrogen actually increase especially at the beginning of flowering. Treat the first two weeks or so of flowing like vegetative growth, don't let n levels get to low early in flowering or you could fall into a pit fall of yellowing leaves that can be difficult to reverse.

The tops are a bit limey as well (3rd pic). I have a garden bed that I am growing in, that I dug a large hole and filled with a mix of FF Happy Frog, FF Ocean Forest and perilite. The rest of the garden is a 50:50 loam and organics mix...but has no perilite added to it. My only other area of concern is that if this isn't a nitrogen deficiency, my plants' roots may have outgrown the FF soil and reached into the 50:50 mix. Perhaps the roots are no longer getting the proper drainage?