I just applied in May and I put the PCC I used during my PR application... however, immediately after I received AOR this month, I was asked to send them PCC for that country. At first I thought perhaps they didn't receive it because their reason was "blank or wrong document".. so I resubmitted the same thing immediate. However, after reading some forums, people said it is valid for 1 year and Canada requires a more recent PCC. I immediately requested for a new PCC and got it the next day and send another webform with the new PCC.
I just received the generic confirmation email that it has been received. I called IRCC to be sure but the agent just told me that as long as I got that email, they have received it and when an agent is working on my file, they will upload it to my file.
I also read somewhere a few days ago that you can also explain why you do not need to submit one which I could have done because that was my country of residence for 7 years so apparently I didn't need to get a new PCC if I explained that. You might be lucky not to get a PCC request.