Help! Any way to root g4 h815 twn-xx with 6.0 v20d locked bootloader?

Any thoughts on the best way to go to get this phone rooted? Back to LP? Any pre-rooted image for 6.0 V20d? Any help will be much appreciated. Unlocking the bootloader is not available on this model, I guess I can live without it. I just want to root it.

Thank you guys!