You were right the first time, John. The following is taken from Walter Lord's "A Night to Remember":
Up on the bridge Rostron knew without asking--yet he felt he had to go through the formalities. He sent for Boxhall, and as the Fourth Officer stood shivering before him, he put it to him: The Titanic has gone down?
Yes--Boxhall's voice broke as he said it--she went down at about 2:30.