good observationsThis looks like Sixth Destroyer Flotilla from the East China Seas Fleet.
155 is unique among 052D as it is a hybrid of Batch 1 and Batch 2 parts. Its mostly a Batch 1 ship but it has the Batch 2 Type 346A radar with the in-array calibration method.
Type 054A 578 and 601 are different batches, even if they both have Type 1130 CIWS.
601 has these changes.
The ECM unit on 701 is upgraded to the Type 726-3 unit used with destroyers.
Something is added on top of the ESM unit.
IFF arrays on the Type 364 radar.
SATCOM antenna is changed.
CEC antenna moved from starboard to port.
also mid deck hanger