OP an independent mainstream can and will force a child out. If they are not keeping up with their peers. As they can just say can’t meet need good bye.
Next year more demands will be on him too - the higher / older they are the worse it gets for a pda child regarding education. As they have to WANT to do it or they are not. Plus the whole anxiety levels too to manage.
I hope that your yr1 teacher is nice and your boy likes him - it can be the making and the breaking.
I strongly advise you to apply for an EHCP yourself. Also, depending on your cash flow situation you might want to get yourself on waiting lists of private people EP, Salt, OT especially if you end up in a tribunal (you don’t need to do that but you will end up with better reports) plus the OT if sensory trained will pick up on lots of other things like noise etc
The EHCP process is supposed to take 20 weeks but honestly it’s generally rubbish and you need to go to a tribunal. Plus LA never give you what they are supposed to and it costs you again.
You might want to give these books to your teacher / senco
The Educator’s Experience of Pathological Demand Avoidance: An Illustrated Guide to Pathological Demand Avoidance and Learning laura kirby
Clare Truman
The Teacher's Introduction to Pathological Demand Avoidance: Essential Strategies for the Classroom
Other people I like to follow Eliza Fricker, N fisher, Heidi Mavir
If you really want him in the independent mainstream - costs a lot but could you pay for a 1 to 1 until the EHCP comes through.
However if he was to do well in the independent mainstream and you went to a tribunal you could try to name the school and then it’s free! (So good to have professional reports for evidence)
Good luck for year 1