Thank You so much for your valuable info, I will surely keep this in mindDon't have to decline the ITA.
Just provide the scanned copy of tracking numbers, delivery confirmation page, application form, credit card payment form for each applicant in Letter of Explanation (LOE) document.
Submit the PR application on the day your ITA expires. CIC usually gives 60 days extension. If it takes longer to get your FBI PCC, you could ask CIC for another extension.
Hope this helps.