Shares of Carnival Corp. /zigman2/quotes/202325446/composite CCL +0.22% rose 1.7% in premarket trading Thursday, after the cruise operator announced more cruise restarts that will increase the use of its U.S.-based capacity to 90% through February 2022. The company said late Wednesday that its Carnival Sunshine ship will restart operations from Charleston on Jan. 13 and its Carnival Liberty ship will restart from Port Canaveral on Feb. 11, adding to the 17 ships scheduled to be operating by the end of 2021. The restarts are part of the Carnival's plan to be using 100% of its cruise capacity from U.S. ports in the spring of 2022. Meanwhile, cruises on Carnival's three remaining U.S.-based ships, Carnival Ecstasy from Jacksonville, Carnival Paradise from Tampa and Carnival Sensation from Mobile, have been cancelled through February. "Our restart plan continues to excel across all metrics, and we are looking forward to completing the restart of the fleet in the new year," said Carnival Cruise Line President Christine Duffy. The stock has gained 3.4 over the past three months through Wednesday, while the S&P 500 /zigman2/quotes/210599714/realtime SPX +0.08% has ticked up 0.1%.