I don't understand why China on the one hand is eager to publish about new Z-10 units but new J-10 and Flanker units are being kept secret up to the point that photo's of newly inducted J-10B's on the internet are not allow to show their unit numbers.
Attack helicopters are more a tactical weapon than a scenario one. That means that they are not as useful as planes as a propaganda and, first of all, they lack the range to appear where they aren`t excpected .
It makes sense to hide weapons that could be useful in a scenario as the South China Sea conflict because they can be a bitter surprise to foreign nations.