After conversion to a Maritime Prepositioning ship the vessel was chartered by the United States Navy's Military Sealift Command until January 2018 as WestPac Express.

After a demonstration in 2001, Austal signed a three-year lease with Military Sealift Command for the WestPac Express.

[1][2][3] In March 2011, the WestPac Express was deployed as part of the US response to the 2011 Tōhoku earthquake and tsunami.

[6][7] In April 2016 WestPac Express was sold to Irish Continental Group, who continued to lease it to the Military Sealift Command until the end of 2017.

[7][8][9] With its charter to the US Navy completed, in January 2018 WestPac Express arrived in Belfast for refurbishment at Harland & Wolff to replace the Jonathan Swift on Irish Ferries' Dublin to Holyhead route.