The leaf could be a sign of a slight deficiency. When plants are lacking something, you usually see it in the lower leaves, as the plant draws the nutrient it needs from the older part when there are too few nutrients in the soil. Since everything else looks super healthy, I would normally continue as is and just remove that one leaf. Water so that the soil has good moisture. With too much water, it gets too little oxygen, and with too little, it can't absorb the nutrients properly. Feel free to lift the pot. If the pot feels light, give it some water again. At this stage, the ladies need about 300-400 ml every three to four days. With your pot size, maybe 500 ml. The roots haven't taken over the pot yet and therefore don't need that much water. This way, the soil always has good moisture for the soil life, and the roots still get enough oxygen.