Now that we get some perspective of the new 130mm gun with sailors standing next to it - it is just Massive! Looks like some sort of ancient artillery piece sticking out of a fort rather than a naval 'gun'.
Hmmvw over on CDF said this is probably the handover ceremony, which I would tend to agree with.
After all, this is still at JNCX rather than the ship's assigned base, and there is no flag handover, little ceremony and fanfare at all.
So I expect 172 will now make its way down to Sanya and actually get commissioned there, hopefully with the honours and circumstance which this ship deserves.
Crazy to think this ship was only launched a year and a half ago... I wonder if 172 is being commissioned quickly so the PLAN can rapidly train its sailors up ready for future 052Ds. I can't imagine that all of the systems on the ship are fully operational.
Edit: lol never mind the photos above show it was a commissioning ceremony... Weird that it wasn't at Sanya.