Hi Dug, this is normal cycle of life, the plant is going to the last stage of her life, leaves yellow and fall down expecially from the bottom canopy. Your girl is gorgeous and plenty of life and like my three outdoor beast girls, your shows the signs of age. Pluck leaves away later, now the leaf in the picture is still doing photosynthesis. Leaves fall will increase day by day. Good luck and stay relaxed, all will be fine. 👊