If all looks good it may be just part of the process for that particular strain. I have 4 Vertigos autos at 77 days and my fan leaves are still green and healthy. I just did a final flush and replaced just PH'ed water with zero nutes, maybe they will start dying off. I kind of hope they do so the light will penetrate deeper into the canopy.
Does your plant have nice tight buds? I can't really tell by your pictures.
Here's mine at 42 days, still airy but still have at least 5 weeks to go. Sorry about the LED light.
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