We will be transitioning to kindergarten this fall, I am very nervous about it. Not so much with his cognitive skills but his social skills I worry so much about.

My son is in high school now. Each and every transition =nerves. Talk to the teacher, go visit the classroom and school in the summer several times. Talk to other Moms. Reach out and attempt to establish relationships however you can. Stop in the school office and introduce your child to them. Be seen so they know who you are and indicate your level of commitment to success of your child. Offer to volunteer if that is possible and you will not be a distraction for you child. Take friendly approach with everyone in the school!
Social skills are a concern we worked hard to make our son be in social situations so he could gradually build them up. He still prefers to be home but he has slowly added skills as the years have passed.
Hope you have a wonderful teacher and that kindergarten is a great start. Hang in there our children are amazing!

We just transitioned to kindergarten in September. It wasn't difficult forums to make the decision because it is a classroom solely for ASD kids. It is difficult however to get my son to do any of the "homework" they would like him to do and it seems like a waste of time to force him to do it. He is however getting speech and OT and his teacher is awesome. The school took the lead on everything so it was a very smooth transition.

I did this a few years ago with both my children, and it went well with one and not with the other. I was in Florida at the time and both of the children were in preschool and had an amazing teacher who worked with them both. My children are a year apart and one is high functioning ASD and one is low. My high functioning son did very well with the transition, all we had to do is explain that he was going to a different classroom and a new teacher but was going to be at the same school. He was a little nervous about it, but we were able to bring him in and meet the teacher and play in the classroom ahead of time so he could get used to it, and there were no issues.
My daughter on the other hand who is non verbal did not do well out of her preschool environment and not with her preferred teacher. We tried bringing her to the class room spending time with the teacher on multiple occasions for multiple hours, but she could just never feel comfortable and would tantrum. My daughter does have very bad transition problems though, so that is why this all happened. She was out of school for 3 months before we moved out of state to MA for better care for her. When we finally got settled which was about a month later we got her into her new school. It took about two weeks of brining her in for an hour, then two then half the day, all with my wife present for her to take to it. Finally my wife was able to drop her off for half the day for a week, and then she was there all day from then on.
Every child is different but what you have to do is to try to make your child comfortable by working with them and bringing them in slow and letting them decide how long they can handle being there. After some trial and error and some patience you should be able to have them transition. I wish you luck and hope this info helps.

We transitioned from Ken Crest to an autistic Kindergarten class. Within a few weeks the teacher said he was too high. So he has been in a regular classroom with special education support (50%) since then.