Welcome to Appeals!

(Thanks, Amber, for the link.)
The first question for an appeal is: does the school accept that she is qualified?
If not, then you are going to have to argue that she should be deemed qualified. How you do that is up to you.
If you go for the minimum ("
just on the grounds that on reflection she probably should have had a qualifying score") - can you be sure whether an independent panel would consider it sufficient?
If you feel you want to play safe, you should start collating as much evidence of high academic ability as possible:
http://www.elevenplusexams.co.uk/appeal ... cation#b11Secondly, if she is deemed qualified, but in the end the year group happens to be oversubscribed -
or could become oversubscribed as a result of the number of potentially successful appeals - you maximise your chances by putting forward some good reasons for wanting a place.
http://www.elevenplusexams.co.uk/appeal ... -school#c2