Queries about priority date at VISA office

[samirk]

Hi All:
Can anyone have idea that what is the priority sequence at visa office...........

Application received date at CIO?
Or, Initial approval (AOR) date of CIO?
Or Full documents received date at visa office?

Suppose after getting AOR from CIO, they provide 120 days to submit full application to visa office with a Immigration File number. Now if any one make two months or more delay to submit full application to visa office then is there any impact on processing time or case is processing at visa office according to the sequence of full application received date.