you can lodge the application for payment up to 3 months before baby due date - it will be pre-processed - so if there is additional information required (bank details, contact with employer) that require follow up, it ca be followed up in advance to prevent delays post birth

proof of birth still needs to be provided, and pre-claiming doesn't speed up the post birth processing. pre-claiming doesn't allow you to "jump the queue" over someone that, for instance, has other children and is only lodging the claim for baby bonus. it just gives you a pre-birth opportunity to make sure all the fiddly bits are done.