Hi OP, we were told our ds had autism at about 18 months (he regressed) and he was diagnosed at two years old. We got a statement in place and he had speach therapy, occupational therapy and a 1:1 in place at nursery. We also kept him in nursery for an extra year then he started reception (kept a chronological year behind). Nursery was given a budget before the statement was in place.
It's horrible, I won't lie. Ifthings play out as are in your head, you'll grieve. Please remember nothing, absolutely nothing is set in stone. You and your child need support and he needs as much support in place as soon as possible.
Apply for an ehcpa yourself now. Use ipsea and sossen. You may have to appeal if the la decline, please do not worry- you'll be fine. The threshold for a needs assessment is very low and I'm sure with what you've said your son will meet it.
Getting the assessment will help you massively. You can request assessments of reasonable needs. You need to request an autism assessment, a speech therapy assessment and an occupational assessment (inc sensory) as a minimum- these are all reasonable. His needs cannot be known if they aren't assessed.
For the speech therapy assessment request an AAC assessment - high-tech. Have a look at prologue and Words for life (watch videos and Google, I'll find you some links and post). It's vital to get some form of comms in place started asap. It won't replace or stop him becoming verbal but will support. The LA may push pecs but they can be used in addition. He will likely need a total communication approach (again google).
Ot- he will very likely have sensory needs which will impact everything he does. These need regulating. He won't be able to learn anything until these needs are met (if he has them). There are many other conditions that go along with autism that ot deals with too eg hypermobility and dyspraxia. He may not have these but how do you know until it's looked at?
You may be entitled to help with nappies and further down the line home adjustments.
If he has dietary restrictions ask for a dietitian too.
as part of the ehcp process you are entitled to social care support- hes only little but it may be somethig to think about later.
having the ehcp in place for school will help with placement.
Another poster mentioned dla. Yes apply. My ds had high rate care from two and high rate mobility from three (under serve mental impairment- see if you can get a prof to support the application and use that language in the letter). The money will really help you.
You are not on your own, look up your local parent carer forum or join some Facebook groups (go for ones specifically about severe autism).
You will be OK, it's a hell of alot of info all at once but you will be OK x