Guandong Huangpu is probably still working through a large order of coast guard ships placed several years ago. If I recall correctly, China is in the midst of an unprecedented expansion of the coast guard fleet, the reason being patrols of the South China Sea's is best conducted by a civilian agency. In fact, I think Huangpu has been building more coast guard ships than naval vessels for a while now.
True. Forgot to add Huangpu also does many of the PLAN auxiliary such as the military tugs, the ELINT ships and the sonar surveillance ships.
I wonder how many of the coast guard version of the 054A is made.