Length of an appeal for schengen visa refusal

Hi i got an internship in the erasmus program and visa git refused. I was advised to appeal. Does anyone know how long an appeal takes?

You have to appeal the refusal within 15 days of notification.

As your visa  was refused they have given you the reason (reasons).

It only makes sense to appeal if the circumstances you claimed have changed.

If you appeal the decision will be given short-term.

Ricky