unabridged birth certificate not out

i app**** for a passport last week so as to travel with my son and was told need to apply for an unabridged birth certificate, now passport is out and unabridged birth certificate they saying 3 months, so how do i travel with my son we are travelling as a family and we normally do so every December . i see there is a travel document that can be issued if the unabridged birth certificate doesn't come out on time but when i called home affairs call center they said only when the 3 months has lapsed. help me how do i get to to travel with my son