satlitegirl my DS is 2.5 and Autumn born so it's not an issue for me but I am interested in this topic and I recall seeing new guidance on this for schools.
I have had a search around the DCSF website and found this press release.
In particular:
For admission to the 2011-12 school year, and subsequent years:
d) parents can request that the date their child is admitted to the school is deferred until later in the school year or until the child reaches compulsory school age in that school year, and
e) parents can request that their child attends part-time until the child reaches compulsory school age.
Deferred entry to primary schools
Admission authorities must allow parents of children who are offered a place at the school before they are of compulsory school age to defer their child's entry until later in the school year. Where entry is deferred, admission authorities must hold the place for that child and not offer it to another child. The parent would not however be able to defer entry beyond the beginning of the term after the child's fifth birthday, nor beyond the academic year for which the original application was accepted. This must be made clear in the admission arrangements for the school.
I think this means that you can apply for reception, guarantee the place and then defer until later in the year. I'm not sure whether they mean you can hold the place into y1. I suppose it depends what exactly "nor beyond the academic year for which the original application was accepted".
Presumably you've missed the recent admission round so it may be different if you are applying outside the normal round.
You might also be interested in the concept of flexi-schooling see here or try a google search.
Also have a look at the home schooling forum as you will find people who have home schooled for several years and then had DCs move into formal education.
I understand that the EYFS is meant to be play based but it is up to you to decide that you can fulfil his needs at home next year.
There are many who think that the EYFS is too much pressure for children - you may be interested in this campaign and this blog.
Maybe someone could give you some real life experience of having a DC in reception but then just not sending them some days/afternoons and saying "sorry it is too much too soon for them" - presumably there is no come back for truenting etc if you are before the legal school age?
(I am actually v.pleased that due to his b'day I will have DS at home with me Thurs & Fri (he is at nursery M,T,W) until he is nearly 5!)