Your answer is partially correct.
Canadaim is not an official CIC website, please refrain from quoting it.
From CIC website it says:
Date the certificate was issued
For the country where you currently live
The police certificate for the country where you currently live:
- must be issued no more than 6 months before the date you submit your application
- must not be expired
For any other country
For any other country, the police certificate must be issued after the last time you stayed there for 6 months or more in a row.
Some countries put expiry dates on their police certificates. If you have a police certificate that expired, include it. We’ll accept it if:
- it was issued after the last time you stayed there for 6 months or more in a row
- it is not for the country where you currently live
An officer may ask for a new one later on.
While the PCC from your current country of residence is valid for 6 months; PCC’s from all other countries will be valid indefinitely provided they don’t have an expiry date and they were issued after you left that country.
For e.g if you lived in a different country in 2012 and you obtained it’s PCC in 2014, and it doesn’t have an expiry date, it would still be valid in 2025. It makes sense because since you no longer live there your criminal history is not bound to change.