Dear rganesh,
"The certificate must be issued no more than three months before you apply".
I understand from the above sentence that the PCC must also accompany with the application to the CIC. But if applicant couldn't send it with the application for any reason and applicant sends it to CIC/Visa Office after his/her application then I believe, the date of receipt of PCC to CIC/Visa Office will be considered but not the date of receipt of the application. Hence, I believe, date of receipt of PCC (not application or AOR date) at CIC/visa Office must fall within the 3 months of the date of issue of PCC otherwise CIC/Visa Office may reject it.
This is my understanding which may be wrong. Any one having similar experience can throw best way forward in such scenarios.
in my case i got my PCC issued just a month earlier before sending the application to CIC. Still i got a PCC request along with MR. So better wait for MR and then action for PCC based on contents of the request mail.