Worried my SN child is struggling after moving into year 1

[1995SENNDMUM]

DS is in year 1 in an Sen school, reception year there went brilliantly and he settled quickly however so far in a different class in year 1 we ve had two days when they ve reported him lashing out at staff so it seems to be he could be struggling with the class swap or adjusting back to the routine after the long summer (one of they days was a phone call from his teacher but he settled back down afterwards).
He rarely behaves this way at home, although happened more in the holidays as we figured the lack of routine. Recently had his teeth checked, nothing seems medically amiss and he's on a week off melatonin but actually sleeping well for him.

He's non verbal, autistic with suspected learning disability and it was an arduous process getting his EHCP originally to get in his school.

School haven't mentioned a behavioural plan yet and I imagine that's the next step (they are all team teach trained there and they haven't got to the point of restraint yet, just distraction/deflecting but the day of the phone call he was crying for quite a long period) but I can't help feeling terrified of his placement failing as there will be nothing else for months or years if at all, and I know I couldn't cope 5 days a week with him having no education. I know Sen schools excluding children is quite rare but struggling not to feel scared of things going downhill after everything it took to get him where he is.
Anyone have any words of encouragement or advice?

Try not to let your worries run away with you. I don’t think you need to worry about permanent exclusion, or even suspension, at this point!

It is very early days. What transition did DS have?

You could request a meeting with the teacher if you are concerned.

Is the provision in DS’s EHCP being provided?

I know I couldn't cope 5 days a week with him having no education.

To reassure you, even if DS’s placement does fail, and actually nothing in your OP leads me to believe you are anywhere near that, you absolutely don’t have to EHE.

They did a straight swap to the new class in September, so it could well be a bit of an adjustment for him and there have been good/better days so rationally it could purely be realising a change is permanent causing a lash out (reception last year was a part time transition for a bit but it went so well I didn't ask about it for the next class).

Yes everything in section F is covered brilliantly by the school and actually there's a couple of things they do of their own accord provision wise that have worked very well and also do more often than the EHCP specifies . It's quite local too so got the set up other parents would certainly kill for honestly.

I know in a practical sense it wouldn't have to be EHE, I think it was the panic of knowing no AP or section 19 scenario is easily viable for him and the sudden change in behaviour when we d been blessed with such a good year last academic year.

I’m surprised the school didn’t do any transition either before or after the summer holidays. It might be worth mentioning that for future reference. At the next AR, you could even look to have it included in the EHCP.

Despite what some LAs think, section 19 provision isn’t limited to certain types of provision. And it doesn’t have to be via a formal AP setting. It has to be suitable. If it isn’t suitable, the LA must offer something else that is. So s19 provision can meet the needs of all DC. But I really wouldn’t worry about that. I think you are a million miles away from a failed placement right now.