The 7th 054A was commissioned today with PLAN ESF as No. 548. According to this article, it was named after the city Yiyang from Province Hunan. There is also a news report here.
We found out some interesting stats on 054A like that its standard displacement is 3600 tons (we previous found out that full displacement is 4053 tons), length is 134 m, width is 16 m and maximum speed is 27 knots.
However, the more interesting is the procurement cycle for PLAN. It reported that this unit was first ordered to be built by HuangPu shipyard in 2006. It was chosen to be named after Yiyang in April of 2009. It was launched in Nov of 2009, started sea trials in May of 2010 and got commissioned in Oct of 2010. So, it takes less than a year to go from launching to commissioning. At the same time, it takes 3 years to go from getting the order to being launched. I'm not sure if the earlier ships of this batch 571 was placed at the same time, so the construction time to launching + preparation work could be much shorter than 3 years.