The China Times reported on this; Kyodo News picked it up:

A Chinese attack submarine and destroyer in November last year shadowed U.S. warships in the Taiwan Strait, sparking a 28-hour standoff that brought the group to a battle-ready halt in the tense waters, a report in a Taiwan daily said Tuesday.

The confrontation occurred as the U.S. Navy aircraft carrier USS Kitty Hawk and other ships in its battle group were heading back to Japan following China’s sudden cancellation of a long-scheduled holiday port call in Hong Kong, the China Times said, citing U.S. military sources.

The carrier strike group encountered Chinese destroyer Shenzhen and a Song-class sub in the strait on Nov. 23, causing the group to halt and ready for battle, as the Chinese vessels also stopped amid the 28-hour confrontation, the Chinese-language daily reported.

Apparently the destroyer and sub were on their way to the historical port call in Japan. The original report was in the China Times, so grain of NaCl may apply.