The battle secured the beachheads of the U.S. Sixth Army on Leyte against attack from the sea, broke the back of Japanese naval power and opened the way for an advance to the Ryukyu Islands in 1945. The only significant Japanese naval operation afterwards was the disastrous Operation Ten-Go in April 1945. Kurita's force had begun the battle with five battleships; when he returned to Japan, only Yamato was combat-worthy. Nishimura's sunken Yamashiro was the last battleship in history to engage another in combat.
Try to answer this question if possible (otherwise reply "unanswerable"): When did Operation Ten-Go occur?
April 1945