I have been doing the tier 3 5v5 tourney.
I JUST NOW (2/24/17 7:30 EST) got a notification on the forum website that:
Tanker, your battle in the Weekly 5v5 February 20 - 24 tournament begins in 2 hours. Get ready!
February 22, 2017 8:09 PM
I am on the forum daily.
Not sure whats up with the notification 2 days later.
Also, (before the patch on Wed 2/22/17) I got two popups in my client about getting ready for the tourney. I got them at the same time.
One said tourney starting in 2 hrs, and the other said tourney starting in 30 min.
Now there were 2 matches that night, so its possible one notification was for each match - but it really confused the heck out of me.
Just FYI WG.