While the FTF method is the safest and most official, there are alternatives for lock removal on the Sony G3312:
To remove the screen lock (Pattern, PIN, or Password) on your using an FTF file , you must flash the device with either a specific "Lock Remove" file or a stock firmware. Sony G3312 Lock Remove Ftf File
In the Wipe pane on the right, ensure USERDATA and CACHE are checked to ensure the lock screen is actually removed. 3. Connect the Phone in Flash Mode Firmware Change/Update on SONY Xperia L1 Dual G3312 While the FTF method is the safest and
That status only prevents custom kernels. Official FTF flashing works 100% of the time on locked bootloaders. Sony G3312 Lock Remove Ftf File