Overfert??

Overfeeding typically affects the entire plant, but your your main issue is localized in the lower, older leaves. This clearly indicates a calcium/magnesium deficiency, primarily calcium (evident from the leaf spots) with early-stage magnesium deficiency (shown by overall yellowing). Have you been using demineralized/distilled water without Cal-Mag supplement? This would certainly cause these deficiencies as such water lacks essential minerals. While the plant can recover, your yields may be impacted due to this deficiency occurring during early flowering. The choice is yours whether to continue or discard it. For fastest correction, I recommend using a synthetic Cal-Mag supplement to provide immediately available nutrients. Remove the severely spotted leaves after treatment begins, this will help you monitor the plant's response to correction. Cal-Mag supplementation is essential for maintaining healthy plants, particularly during the flowering stage. You have two effective options: -Organic supplements (ideal when used from the beginning to prevent deficiencies) -Synthetic formulas (for faster correction when needed) Whichever you choose, consistent application is crucial, always monitor your plants response and adjust accordingly. Remember, prevention is easier than correction when it comes to nutrient deficiencies.