I would not say there are plenty of older JIANGHU’s. As I recently mentioned, the only JIANGHU I’s in service is 516 serving at Ningde as fire support ship and 519 at Huludao as test ship.
Then there are the six remaining JIANGHU II 533, 534, 543, 545, 553 and 555, 557 at Yulin, adapted to the role of South China Sea patrol frigates, JIANGHU III 537 remaining after the sale of her two sisters to Bangladesh, and JIANGHU IV 544 at Lushun serving as Naval Academy training ship.
The JIANGHU I/II’s at Lushun have been replaced by JIANGWEI II 564 and 565, those at Shanghai-Wusong by JIANGWEI I 539-542 , and those at Ningde by JIANGHU V 558, 559 and JIANGWEI II 566, 567.