With that level I would strongly urge you to look at specialist provision. It seems likely they have an MLD and I can tell you as a secondary SENCo you aren’t doing them any favours sending them to a mainstream school with this ability. It really affects their self esteem once they realise how below everyone else they are, no matter how much they get out of the school from a social perspective. They are constantly in interventions, doing completely separate work. They will not be able to take GCSEs eithwr. I am currently in a situation with a Y8 and 11 who are needing specialist provision but it is so so hard to place out of year. The y8 we will have saved just in time but the y11 is now school refusing and has severe mental health difficulties. But he came to us without an EHCP in y9. Best wishes, Amy.