4seamer, you didn't just jump him over 13u, you skipped 12u as well.
I just had my son skip 13u, but it was so he could play with his grade and get on the big field, plus he's 5'9, he really had no business swinging anything but a BBCOR!
The transition has gone well. His throw downs are spot on from behind the plate, and while he has seen a major improvement in pitching accuracy from 12u he has noticed that the backstops seem to have gotten MUCH further away! His curve ball breaks better than ever from the mound, and he's still able to hit the gaps to both sides, plus he loves that the gaps are even bigger!
No complaints about skipping over 13u from him, as for me, I like that he isn't the biggest one on the team anymore :- )