Thank you for your insight and advice, ladies. MN really is proving to be a lifeline at the moment.
The SENCo emailed me back a short while ago in response to my email (I'd already aent it, btw!). He is off until Thursday, so will read my request for assessment then and respond. To be honest, I am sending it off on Friday with or without his input and i have said that (albeit slightly more politely).
The Exclusions Officer is phoning the school tomorrow, so will chase up to check that has happened and find out what was said.
I don't really know what I can expect in the short term. That's part of the problem - what am I asking for, really? But you're all right - it's the long term goal I have to keep in mind.
I have put together a file today with all the relevant professional reports, correspondence etc and a timeline stating what happened when. I am now going to keep a file with notes for every meeting / phonecall etc that takes place. At least this has forced me to get organised.
No reply from IPSEA earlier on, but am going to give them a try now as their advice line is open between 7-9pm, apparently. the guy from SOS:SEN was fab. Told me to keep harassing the LEA and not to allow them to fob me off. Gave me a bit of that fighting spirit.
I am naive to all of this, I realise now, but I just cannot believe that the standard response to a troubled 5 yr old is to send him home. It seems so very wrong.
Thanks again, all. You have no idea how helpful it is to have you as a sounding board!