I provide some links below - any questions you have are likely to be answered in the Q&As.
1) do we have a strong case for an appeal and the school said they will give her a 2.1?
It depends on the totality of the academic evidence:http://www.elevenplusexams.co.uk/appeal ... cation#b11
For headteacher recommendations, scroll down to (d):http://www.elevenplusexams.co.uk/appeal ... laneous#e9
2) We understand there are two types of appeals, a selection review behind closed door and an appeal review in front of a panel where we have an opportunity to explain our circumstances. Is this true and what is the difference.http://www.elevenplusexams.co.uk/appeal ... aneous#e32http://www.elevenplusexams.co.uk/appeal ... aneous#e33
3) if we go ahead with the appeal do we have to select our preferred grammar school as the first choice, as our concern is that we may lose out on our preferred non-grammar if we lose the appeal.http://www.elevenplusexams.co.uk/appeal ... aneous#e35
You cannot lose out on your preferred non-grammar by putting a grammar school first (and then appealing unsuccessfully).