How long does it take Adoption Assistance To kick in..

After you signed the Adoption Placement Papers? I have been fostering my children for two years. I signed APP papers on april 17th. I still have not received payment for April 18 to May through Adoption Assistance. I just wanted to know is this a normal delay because they are just entering the system or should i call my Adoption Social Worker. We finalize May 20th. I just want to make sure that everything is taken care of. I live in Sacramento County.