If you have the courier delivery confirmation, then you can be rest assured that the package has been received by OINP. Once OINP clears the backlog, they shall look into your package. Once they are sure that all documents are submitted (not completeness check), they shall send you Acknowledgement of Receipt (AOR) along with receipt for processing fee (CAD 1500). Once the AOR has been issued, OINP takes up to 90 days to do a completeness check.
For your information, I got my AOR after 111 days since the package had been delivered to OINP.