With what I have gathered on the forum, backgrounds usually starts when ELIGIBILITY has been passed, why would they start background/security and spending money and resource if PA's eligibility is not passed? So, common sense says everything starts after Pre-Arrival. Here is good thread you could read that explains the Security/Background check:Are background checks ALWAYS done at the end of someones app? is it possible they sometimes are done at the beginning or middle part of ones app? Because some people get ppr a week after pre-arrival and others sometimes months. so im wondering if the ones who get ppr a week after pre-arrival maybe had their background check done in earlier stages of their app? and the ones who waited months after pre-arrival had to wait for the background to clear? whats the diff between background and security check?
https://www.canadavisa.com/canada-immigration-discussion-board/threads/background-checks-explained.39578/