I will try to explain it a bit more clearly...
Our grammar schools have no catchment. The neighbouring LEA has grammars but have a catchment. Many children in the neighbouring LEA will put their local grammar school down as first preference and one of ours down as second preference. This means that many of the children within the 310 highest scoring in our 11 plus will also pass the 11 plus for their local grammar and be offered a place there because it is their first preference. So although there are 310 places, at first allocations in March last year, places were offered at our grammars to 310 children but the lowest ranked child offered was 359, because 49 children who came higher had gotten into their first preference elsewhere.
The LEA then said it was possible for the children ranked 360-370 to go on to a reallocation list for the grammar schools. Some of these children did not wish to be placed on the reallocation list and decided to stay at their local comp instead. Some of these children were offered places by September because other children who had places at the grammar as a first preference took up independent school scholarships between March and July, moved house or decided they rather go to the local comp.
So even though she has come 75 places below the 310, the reality is that she is extremely near to the lowest ranking child who will be offered a place at the school. At appeal, the school would look at her score compared to the lowest ranking child who had got in without reallocation, which could be, for example rank 364 to her rank 385. As most people will decided not to appeal, it could be that she is the highest ranking child to appeal.
Now to come on to the other point, DD doesn't really need to go to a grammar school. If she had answered one more question correctly, she would have got in. But she would always have been borderline for getting in. She would never have gotten an amazingly high score in the 11 plus. For any other child in that situation, I would be thinking that a child who scores that highly would be in the top 15% of children (and DD was not tutored), so once the top 10% of children have gone to grammar school, she should be in the top set at the comp.
But that is not going to happen with DD. For French, Geography, History etc, she should be in top set because they are based on her CAT scores which will be similar to the 11plus. For Maths, Science and English, she will be in low sets because her predicted SATs results are low. Now, I know that 11plus maths and VR measure a different thing to the SATs, but I don't think the difference between the two should be such a gulf. So am I left with a choice between appealing for the grammar (where she will be one of the least able) or sending her to the comp where she will be in low sets for half her academic subjects. In some of her national curriculum sub levels she made no progress at all between end of year 4 and end of year 5.
So I can teach her at home how to do the Maths (although I don't understand what the problem actually is as she did well in the 11 plus Maths) and the reading test, but her Science and writing will be based on teacher judgement, and she has the same teacher as she did last year.
So rather than appeal, I'd rather resolve why there is such a big difference between her 11 plus result and her national curriculum levels with either the primary school or the comprehensive school she is going to, but I'm not really sure how to go about that. But I certainly don't have the choice between bottom of the grammar and top of the comp.
Thanks to anyone who has bothered to read all of that.