My DS had a mid-year skip 1st to 2nd. I cannot say enough about the positive social benefit. In fact, if we had to do it all over again, we would do it FOR the social. We had no idea how disconnected and lonely he felt until he was in 2nd and hit his stride. Now, going into 4th, his best friends are the two oldest kids in his grade and one of them is also a DYS. Academically, he could skip at least one more grade right now but there's no reason to upset the social balance he's mastered right now. We decided to homeschool instead but he is still best of friends with his former classmates.