@Idontgetit33 I think this has become very confusing because @BrumToTheRescue is telling you what the legal process is and most other people are telling you what they think might happen in their LA.
The law is the same all over the country. The legislation is Part 3 of the Children and Families Act 2014. The SEN Code of Practice Here puts that into a more easily read guide. Anywhere you see 'must' means that the LA has to do it. Anywhere you see 'should' means that if they don't, the LA would have to justify why they didn't at Tribunal.
At your phase transfer review (the annual review of your child's EHCP in their last year of primary school), you will be issued with a draft EHCP, and asked to make any comments on the draft. At that point, you will also be asked which school you would like to be named on the EHCP.
Think about whether you want your DS to continue in Mainstream, or if you would like him to attend a Special School - Special School places are not easy to get and you need to be building the evidence now if you want one.
If you want him to continue in Mainstream, go along and start looking this year at the schools - they will have open days for the current year 5s heading for year 6, and that's a good opportunity to look at what they're 'selling' to the parents. Ask about their SEN provision, generally. Check out their attitude to SEN - does it get mentioned, or do they bang on about their 'high achievers'? Look at their behaviour policies - do they show a good awareness of SEN and how it can impact behaviour?
When you receive the draft, you will name the school you want to. The LA must name it unless they can show that it is unable to meet your child's needs, or to admit your child would be incompatible with an efficient use of resources.