The guided-missile destroyer operated normally and did not conduct the transit under the rules of an innocent passage – the restrictions that allow a warship to pass through another country’s territorial waters with no notice.
The ship was within 12 nautical miles of Mischief Reef for about 90 minutes zig-zagging in the water near the installation. At one point during the operation, the ship’s crew conducted a man overboard drill, a U.S. official told USNI News.
I'm not clear whether the zig-zagging or the drill counted as conducting routine warship activities.
Regardless, the article specifically notes that this was beyond innocent passage so I'll go with that.
Well, I said I'd wait to hear details about this operation to see if it was more of the same.
It seems that the emphasis in this operation about the nature of the FONOP highlights that past operations in the South China Sea were mere innocent passage missions.