More interview with JP TV. The interview was probably last summer, but at the time he said he had no more than 6 years of skating.
https://twitter.com/NathanChenJP/status/1252888043427491840
https://www.instagram.com/p/B_SAsf6JWQu/
https://twitter.com/NathanChenJP/status/1252888043427491840
https://www.instagram.com/p/B_SAsf6JWQu/