Sony kicks off Android 8.0 Oreo rollout for Xperia XA1, XA1 Plus and XA1 Ultra

Although we don't know much about what other changes have been included in the update aside from the usual Android Oreo improvements, we do know for sure that it includes the February security patch.
Keep in mind that the update is pushed OTA (over the air) and weighs in at 900MB, so free up enough storage before attempting to download it. Also, make sure that your battery is at least half charged since the installation may take some time.
source: XperiaBlog