birth father has done nothing

Please someone let me know if in the state of Maryland there is a legal timeframe for a birth father to take action in order to prevent an adoption.On Maryland Statue it states consent is not needed:The child has been out of the parent's custody for 1 year, and is in the custody of a child-placing agency. The child has been out of the parent's custody for 1 year, and has formed a significant attachment to the petitioner. The child has been abandoned. The parent has failed to maintain meaningful contact with the child or to support the child. The parent has been convicted of child abuse or a crime of violence against a child The baby in question is now 22 months old..and has been with us since birth. The birth father has wavered in his decision. Only seeing the baby through us, once in all this time. He has gone from wanting to give up the child, to open adoption and now several months back wanting the child. Since he has basically done nothing but states he is awaiting for this to go back to court...what chances does he have? I question his commitment he has known from day one, that the child was placed with us for adoption. Wouldn't he have to atleast push to get this into court or push for visitation, or push for something???Please let us know...thank you