I got my final decision May 25th, Tracker is till down and the IRCC login also shows the same as you- where it says still in progress for background check. I didn't get any additional emails- however in the automatic response from the p1 email I responded to, it says they are currently having "significant delays" with eCOPRS".
I saw my update via IRCC login just checking myself since the tracker has been down and then I randomly for the P1 email today. Looks similar to when there's been an update to your account except you respond directly to that email.
From my understanding, once you get that Final Decision and P1- you're set in stone. If there was concerns before they do final decision- I believe you would have known such as needing more information or an interview request.
Pre- Congradulations to us!