I have friend who teachers piano at dd school. The norm at the school is y3 and above. But dd (y1) is very keen to learn and is always playing the piano at home. My friend is worried that she will get into bad habit with the fingering making it hard when she starts lesson. She has ask me if I what her to start early in y2 (she will be 6.5) as she will need to clear it with dd teacher and make space for dd for September.
I'm not sure if it's a little young or if she is keen to go with it.