If you are not using it already, you should integrate adwhirl into your application, it will choose between iad and admob automatically. Now, just because you submit requests does not necessarily mean that they are going to fill, so admob will not always show. Also make sure that you have all the requirements for iad filled in on itunes connect, if you do not have taxes, etc. A filled apple will not send you any announcements.
Hope that answers your question, sorry, I'm a little unclear about what you are asking.