hi freefrommum, your post has reminded me that I said I would give you an update on how I got on with DDs school.
DD is only allergic to milk (although possibly nuts as well) so a bit easier than you but the following are the main points that came out of my meeting.
The school does not routinely offer milk to reception children but if any are left over from the nursery it would be brought into the reception classes. There are two classes in each year group so the first suggestion was that a 'milk bar' could be set up in the other classroom so that DD wouldn't have to come into contact with it. Then DDs teacher said 'yes but if it was a nut product we would ban it' (they have a nut ban in place at the school). The assistant head said straight away 'well no milk will come into reception, we will give any left overs to Yr 1 instead'. Great, problem solved! the only issue is that DD drinks a couple of cartons of flavoured soya milk a day (if nothing else for the calcium) but the school are happy for her to drink chocolate soya milk whislt everyone else will have to get by on water!
As to lunch, I know of a couple of children who are dairy intolerant who will be in her year and so I suggested the 'buddy system' whereby any children not having dairy in their lunch could sit together. We would obviously have more to gain as like your DS, DD reacts on contact but I would have thought the other parents might be reasonably OK with the idea. The senco vetoed it on the grounds that the school has an inclusion policy and having an 'allergy table' would not be very inclusive!
So their plans are for DD to sit at the end of a table in the main dining hall. There are always adults in there so one will set next to her and they will try and put milk 'sensitive' children near her. The Reception children go in for lunch first so the tables should be clean.
I guess for now I am OK with what they have suggested but will keep an eye on things once term is underway.
I took plenty of notes with me to the meeting including hard copies of the anaphylaxis campaign's protocol and Allergy UKs protocol as I'd heard from a friend that the school didn't have anything formal in place. I suggested that they might want to draw up something similar.
I also gave them a sheet outlining DDs allergy(s) and how she reacts and how I would expect her to be treated. I will see what they have drawn up when September comes
good luck with your meeting and I hope the school can meet your requests in a way that can work for you