You can't apply before three months before your due date. So for me, my edd is 23/10, I can apply as of today. Or, because I'm also getting employer maternity leave, I can wait until baby is born and apply then with paper forms.

If you were to try and lodge the claim today, it would ask "are you expecting a child on or before 23/10/2013?" Or something along those lines.

Hope that helps!