At this moment Android Oreo has been released only for phones produced by Google and we don't know which company will configure Android 8.0 for their devices as first firm. Due to the transaction between Lenovo and Motorola owners of Motorola's phones are uncertain if purchase of Motorola by Lenovo will be good for customers, especially when it comes for topic of updates. Now you can check if your phone will receive update of Android system to Oreo version, because Motorola officially published on their blog information which devices will receive this update.
These devices are: Moto Z, Moto Z Droid, Moto Z Force Droid, Moto Z Play, Moto Z Play Droid, Moto Z2 Play, Moto Z2 Force Edition, Moto X4, Moto G5, Moto G5 Plus, Moto G5S and Moto G5S Plus. At this moment Motorola haven't said when company exactly plans to release updates for previously mentioned phones, and we must wait for this information.