Yesterday, NTT DoCoMo finally released Android7.0 for SC-02H, SC-02H is an identifier of Galaxy S7 edge as DoCoMo smartphone. This Android is not 7.1.1 but 7.0 which includes security patches until March 1.
The upgrading itself is very easy and takes about forty minutes. If you do it while your sleeping, you should turn off Display Lock feature during the upgrading because it needs to reboot the system and then App optimization.