This probably isn't new to this version, and might be an upstream issue, but when the private space PIN is different from the device screen lock, if I power off while a private space app is up on screen, the "Enter your device PIN" screen will show up for a second before the screen properly goes off. This doesn't happen if I exit out of the private space app first, and doesn't happen if the private space lock is set to the same as device screen lock.
It doesn't really break anything, but it's not proper behavior either way and might be worth looking into (and reporting to upstream if needed.)