It just got 8.0 a couple of weeks ago. I don't recall seeing anywhere that Motorola will commit to 9.0 on the Z2 Play.
For what it's worth, the Verizon edition isn't even on 8.0 yet. :-/
Motorola says that the Z series phones should get 2 system updates. If Motorola follows through with this promise the Z2 play should get Pie, but probably not until next spring at the earliest. An interesting fact, the original Z play got Oreo 2 months before the Z2 Play.