Just a theory - may be it's the bots now doing the stuff that could be done without manual intervention (except the review of eligibility which is started automatically by the bot but will be concluded by a reviewing officer later on as approval/rejection) especially from the high demand areas (India, China etc.)In the past, BVL always preceded a rejection at a few minutes apart or within 48 hours. However, if it is approved the PPR can actually take a few weeks/months. This is how people concluded that a decision has been made. This is not backed by any documented process by IRCC and only an observation. We don't know if they might have actually changed their process as some people including me have received BVL after 4-7 days of application. So either we are instantly rejected or something else. Only time will tell.
Source:
https://www.canada.ca/en/immigration-refugees-citizenship/corporate/transparency/access-information-privacy/privacy-impact-assessment/use-computer-analytics-ircc-programs.html