Upon her return to Hawaii from San Francisco, California, on 3 December, "Signet" began a three-week period of availability, followed by patrols and exercises in the islands. On the morning of 22 January 1945, she sortied with the escorts of a convoy of 39 LSTs, LSMs, and LCIs bound for Eniwetok. The convoy arrived on 3 February and, after a day of logistics, "Signet" got underway for the Marianas en route to the Iwo Jima invasion. "Signet" saw her charges into Saipan Harbor on the 10th, then joined Sweep Unit 2 at Tinian. She stayed there four days, then sortied with Mine Unit 1 on 13 February headed for Iwo Jima in the Volcano Islands.