My smartphone is SC-02H which is a name of Galaxy S7 edge by docomo. Its OS is Android 7.0 now though it was Android 6.0 when I bought the smartphone. On 2017.Oct.18, docomo announced they would give Android 8.0 to it someday in the future. I do not know when exactly because it is always late that they give a custom OS. But for that, I try to create a full-backup of android7 by adb.exe.