"I believe that regardless of the actual birth date, they just assigned the next sequential number when the birth registration was processed. I don’t think there is necessarily any attempt on their part to order them by birth date."
There are a number of explanations that explain this. The Registrar simply assigned the numbers to the birth registrations as he/she pulled them out of their in-basket.
Okubo said they processed the BC’s they had on the same day they received them. Obama’s was supposedly received 3 days before the Nordyke twins’ were received. His had been in the file numbered for 2 full days before the Nordyke certs ever showed up. So how did he get a later number than theirs?