Just got heavy into JM's last year

For those growers , with 2G crop with a single leader that is 5-6++ feet +, is is the same scion that started off smaller from a liner to 1G. Or does the grower take a larger scion length cutting when grafting. I've received stuff in a 2G that is a almost from floor to about 7-8 feet high at times.

Just wondering as I've seen all sorts of leader heights via mailorder (which is mainly how I've been receiving them ) due to lack of availability locally.