Nutrients decifit?

Hi buddy. She is short on the marco nute side. Mobile nutes. Marco nutes like N-P-K are what are called mobile nutes, and an otherwise healthy looking plant that is just a little short of what she needs and not getting it from the SUB, the new growth, (bud sites), will take needs mobile nutes from old growth, it's Just a sign that things below just need a little top up. It's actually a good thing to see if you catch it quick means your plant is working at full steam and no nute lock or excess salt build up, love it. A little extra P-K boost and she'll burst back into life. Give about an extra 1/3 of what you normally give. As your plant moves into heavier flowering you should be increasing the overall P-K. Good luck buddy.

Yes, phosphorous and potassium deficiency. A P/K booster will help reduce any further progression, but the affected leaves won't recover, however they won't get worse.