All android software update announcements can be found here → https://yescrowd.optus.com.au/t5/Blog/Android-Software-Updates-12-10-2017/ba-p/328082. At this time the most current version of Android for XZ Premium on Optus handsets is Android 7.0. Keep an eye on our more blog for more info.
again @Dan_C references outdated blogs. if you have a look at the latest android software blog on yes crowd at https://yescrowd.optus.com.au/t5/Blog/bg-p/Announcements/label-name/Android%20Software%20Updates optus did a sneaky update yesterday showing the xz premium is expecting its Oreo update "mid november"
@SteveV You're really calling me out on this one I apologise once again for the misinformation. My brain & body was still in the process of adjusting to my overnight work schedule. Forgive the obvious minor cognitive impairment whilst I was mashing away at the keyboard on little to no sleep