Given Sarno’s post yesterday (Sunday) entitled " A New Boss Fight Track Coming Next Week", I’d say it’s a safe bet that it’s dropping this week, subject to any possible last minute changes of course.
That’s the joy and disappointment of every patch announcement. The joy of knowing it’s on the way and the disappointment that it’s not already here. 
I have to say, LE is the only ARPG where I feel enthusiastic and eager to play after every set of patch notes. 