so, it seems China will continue build 054AG together with new 054B ... thats interesting
So there will be 50 054A/AG and wondering how many 054B will be built total, I think unlikely to get to 50
Very hard to say, old ships will be retired while new ships are being built. There are still some old type 053 in service, and the 2 type 054 probably will be retired soon after 2035. Eventually all variants of type 054A will be replaced by type 054B, and probably also by another new variant or new class of frigates.
If PLAN aimed to have 60 to 70 frigates after 2030, we might see sum total of different variants of type 054B exceeding total number of type 054A built. I expect type 054B will be built for a period of 15 to 20 years before a new class emerge for mass construction.
And changes in political tension and possible conflict or war will affect PLAN's decision on the number of ships to be built. IF China-US relations becomes friendly again, the construction rates will be reduced but we won't likely able to see that in next 5 to 10 years.