"Stephen Potter" screened the carriers as they launched strikes on 21 and 22 April supporting the assault on Hollandia, New Guinea. At the end of the month, they returned again to bomb Truk. "Stephen Potter", and were steaming south of Truk on 30 April when "MacDonough" made a radar contact on a submarine, which soon disappeared as the enemy submerged. Sonar contact was made, and "MacDonough" made two depth charge attacks. "Stephen Potter" came to assist with an attack, and a plane from "Monterey" gave its support. Several deep explosions were heard, and much oil and debris came to the surface as sunk. On 1 May, the destroyer participated in the bombardment of Ponape Island in the Carolines. The task force refueled and rearmed at Majuro and, on 19 and 20 May, attacked Marcus Island before bombing Wake Island on 23 May. The ships returned to Eniwetok for refit in preparation for the Mariana Islands campaign.