The China Defense Blog has new photos of a trimaran vessel built for the Chinese Navy. They also report that this is to be a rescue vessel. Certainly its armament appears modest, and it doesn’t appear to be much longer than a Webber class Fast Response Cutter.
It features cutouts in the sides of the outer hulls that appear designed to allow retrieving persons from the water, much like those on a motor surf boat, in addition to two RHIBs, and a small helo deck.
But this is a Navy ship, not a “coast guard” ship. I suspect this vessel may be used as plane guard for their new aircraft carrier as they work to develop a cadre of trained carrier pilots.
At least two different hull numbers have been seen. We have seen and discussed this type before:

