After CIO (Centralised Intake Office) Sydney, NS process your application, initiates your BG check, and issues you your AOR, your file is transferred to your local IRCC DN (Domestic Network) office. Files may be moved around within the IRCC Domestic Network for load balancing. Also, some applications may be processed by CPC (Case Processing Center) Sydney, NS as well.
My citizenship application is been processed at Sydney office, the test came from Edmonton office that's what the IRCC agent told me when I called. I applied from Edmonton .