When is you daughter's birthday? And how does it correspond to school term dates?
Your child does not have to be in education until the term AFTER her 5th birthday. So if e.g. her birthday was in january, and the sabbatical was for Mid Jan - mid April, you might be really lucky and just get to defer taking up her Reception place until after Easter (which is perfectly allowed).
It would mean, though, that you couldn't send her to school for the autumn term, because, while it is possible not to start until after Easter and keep your place, you can't start, then stop and still keep your place IYSWIM.
Of course, if she is born in December, she has to be in school in January, and the above doesn't apply. But if the dates fall correctly, you might be able to wangle it!
(Oh bother, just Googled and found that Easter this year is as early as it can possibly be, pretty much, which gives you less leeway. You might be able to go for most of the sabbatical and come back a week or so early for the start of the Summer term?)