Lol, SSF is also getting the next 2 054As, so they will have 4. All the new DDGs are also going into SSF. Actually, the new DDGs got added into far before those 051s got retired. So, it follows that DDGs get added first and then DDGs get retired first. And then FFGs get added and FFGs get retired.The rank of all DDGs in PLAN are the same.
As the new DDGs commissioning, the Destroyer squadrons of PLAN are expanding. The first decommissioned 051 class was 105 Jinan, decommissioned in late 2007, at that time new DDGs already commissioned for a while. Now the 2nd destroyer squadron in South Sea Fleet got 2 054As, their 051 161 Changsha decommissioned, 162 Nanning is said to be decommissioned soon. But none of the Jianghu in this squadron decommissioned.
Anyway, the Jianghus will be decommissioned sooner or later. But currently most Jianghus (Jianghu II, III and V) are less than 30 years old, and they are much cheaper to operate than 051s.
Currently the 053s that decommissioned were belong to base units. I think PLAN is cutting base units down while expanding sea going units.
And I don't think you get the real story here, which is the tremendous expansion of SSF. Why is that happening? Well, the reason is that we are going to have an ocean going fleet split out of the SSF. You might want to stop accepting what people tell you on Chinese forums and think a little bit.