Hi MLL,
I have posted and/or read your threads before as I have a DS with a serious speech disorder and language processing problem (CP, etc). Here are some random musings...
Does Lucy have a statement? (genuine Q) My DS is currently going through process, we will be going to tribunal as the LEA have made some very poor decisions.
I always wanted DS to attend mainstream school, he is currently at a nursery at a pre-prep. (btw jajas the school are doing their utmost to enable DS to get a statement and remain supported within their school) But for his type of speech disorder he is better in a specialist speech unit attached to a mainstream school (so similar to the ASD one you have seen) - there is one fairly locally we are fighting for a place there.
A standard mainstream school would not be right for DS, it would be like me attending a school where the main language was Japanese when I only had a few words of the language (clumsy anology, but do you see what I mean).
Do you have a speech unit near you?
To reassure you about the school with the ASD unit, some of my DS' friends from the SN nursery went to the ASD unit attached to a local school BUT only those who were deemed able to cope within the m/s educational system. Several are at the local SN school as they need more support than could be offered in m/s.
I do think you are very anxious, but with the best intentions as you seems to want the very best for your DD. You do realise that if she goes to any school, be it private or state you may, one day, have to buy her a pair of jeans .