You said that you "chose" to take your son out of that school and home school him. Since that was your CHOICE, then you have no case for anything.
Even if you had stayed, I do not see that the school did anything wrong. You said that your son had an IEP, and you said that the doctors made "suggestions" for full day service and continuity, but you have not said exactly what the requirements are in the IEP.
When the IEP is being negotiated and written, the school is allowed to disagree with you and with your doctor. If you and the school cannot resolve those disagreements, then you may wind up filing an appeal just over what the IEP should say. But if the IEP eventually gets written (and I assume it did, since you said you had one), then whatever the IEP says is supposed to be followed.
Having an IEP does not mean that your son may not be disciplined or may not be suspended. He may, if he breaks a school rule.
The school may not unilaterally change your son's placement and send him to a different school. The school may suggest it, may present it to you, may recommend it, may even push hard for it. This kind of change would require an agreement of the IEP team. If the majority of the team agrees that the change is necessary, but you do not, you would have the right to appeal the change to the Special Ed. appeals board for your state.
But since you chose to take him out of the school system, you have nothing to appeal any more.