Hi, DS3 is currently being assessed for ASD, it's his second time around as his previous school wasn't very supportive and their report was a work of fiction. This time however, we have the full backing of his school.
As far as the assessment process goes in my area it is referred to as SCAP - social communication assessment pathway, we have the paed report, the SALT report, ed psych report, school report (usually from connors questionnaire or similar sort if questionnaire) and parents report (similar process to school) - the different reports and assessments are all gathered together and the SCAP make the diagnosis from there. That's the basic pathway.
I have known something was wrong with DS3 since he was 2, and for a long time I was told I was being silly etc. His primary school were not very good with him on the whole, he had one great teacher who originally raised concerns but when she left the school they were no longer bothered. Bad news over, his current school are so fantastic I could literally kiss each and every one of the staff on a daily basis if it wouldnt be so inappropriate
the strategies they have put in place for my son have made him in to a different child! He is much more comfortable in himself knowing there are 'safe' zones in school and people he can go to whatever the problem may be. They, and his medical team fully expect an ASD diagnosis to come from the current SCAP and the school will be able to bring in outside help from the specialist school nearby for him when that happens.
Although it can be devastating and overwhelming at the same time as relieved someone is listening to you when you hear an ASD assessment in in the works it's important to focus on the positives, and the positives are definitely there. During the assessment everyone should get a better picture of what can be done to help your DS, I found over all the process helped me understand my DS3 better.
I hope things go really well for you and you get all the answers and all the help you need.