The 10.2 PTR has been updated with Season 3 and the affixes look to be Fortified, Sanguine and Incorporeal!
By this, it looks like the Mythic+ rotation hasn't changed from Season 2 and the affixes are likely Fortified, Sanguine and Incorporeal.
For this week going in undergeared, make sure to bring a comp that has some Hard CC's to deal with Incorporeal and knocks are a big bonus as well.
Don't forget that Sanguine was recently nerfed!