sorry, it was a mistake. sth wrong with my computer. I want to delete it yet did not succeed. Anyway. It is true that with 500 hours in Alliance Francaise, you will meet difficulties in your study. Yet generally, one can overcome this in 2 or 3 month. French is similar to English to some extend.
School do not need the certificate of language school at all unless they invite you for an interview. In that case, a certificate means nothing. Even if you live in France for one year, you can not compete with French natives.
A certificate is for the ambassade. Several years ago there is no such requirement. Yet schools complain that some students speak awful french. So the ambassade implement such rules in recent years.