To late to clone?

Do y'all think it improves anything to put her in 48 hours of darkness before the chop?

This is my first grow. The plant I have a question about is GDP photo and is on day 23. I transplanted it on day 2, and it in in a mix of 2/3 For Farms Ocean Forest, 1/3 Royal Gold Tupur. Temp 78-80, Humidity 55-60%. I watered approx 40 ounces out of a 1 Gal mix of 2ml House and Garden Amino treatment, 4ml CalMag, 1 Heaping tablespoon of Molasses Ph-6.4 PPM-498 on day 21 when I transplanted. I noticed this on the plant today. It’s on multiple leafs throughout the plant. Any and all help is greatly appreciated. Thanks