FASTBOAT; I checked my go-to forum for English Language Chinese Defense stuff: China Defense Forum:
http://www.china-defense.com/smf/index.php
They have a 74-page thread devoted to the ZTZ-99 family (ZTZ-99 is the official chinese name of the 'Type 99'); and they have your "Chinese TYPE 99AZ or KM with 155mm MG.jpg (2 of 2)" on Page 68 of it, with a posting date of 25 August 2014.
The only things about it that the community commented on was that the CITV-clone and laser rangefinder / millimetric radar rangefinder above the main gun were covered by canvas for security reasons.
There's no ZTZ-99AZ or ZTZ-99KM with a 155mm main gun; nope.
What there IS is a development program for a 140mm tank gun ---it's been referenced in chinese documents, and back in 2005/2006, images of a ZTZ-98 or ZTZ-99 (unsure as to which version) with a 140mm gun appeared on the internet.
It's been a while since I checked CDF; but here's the quick and dirty:
A few more images of the early ZTZ-99 prototypes (including one with ATGMs on the side of the turret) have appeared.
The PLA does field-uparmoring of vehicles -- in a CCTV documentary; they showed engineer troops attached to armor units adding Heavy ERA to their ZTZ-59Bs (Type 59 was redesignated).
More information have appeared on interior shots of ZTZ-99 allowing more accurate armor estimates; as well as better details of just what is in that long bustle.
Rumors of a bustle autoloader in development for the ZTZ-99 have been so far unfounded.
Production of ZTZ-99 continues; more units are being re-equipped with it and it's achieving maturity with the PLA Armored Corps; but lately the hot focus of AFV development seems to have shifted onto lighter units; such as that new mystery light tank.