Talk of stationing 052C/Ds or any warship at disputed islands is just plain silly.
A warship like 052C/D doesn't need to be physically parked at an island to be able to effectively defend it with its weapons (by the same token, a warship doesn't need to be anywhere near an island or coast to be able to put it at risk of imminent attack, which is a big part of why China finds the so-call FON patrols so objectionable. It would be equivalent to someone who lives across town coming over and walking along your fence with his biggest gun and eyeing you menancingly. Sure it might not be explicitly illegal, but you have to be silly to think there isn't a massive amount of implicit threat and attempted intimidation at play as well).
One of the primary advantages of warships is that they are highly mobile, making it hard for enemies to locate and target them.
As such, it makes zero sense to tie those ships down and park them at an island, which adds almost nothing to the warship's ability to protect the island while removing one of the warship's primary tactic advantages.
To do so is to effectively invite a modern day Pearl Harbour.
Given the fact that every time the USN has conducted FON patrols, PLAN primary surface combatants have been on hand to shadow them at close proximity, it's a good bet that all of China's new islands are always well covered by multiple PLAN warships patrolling in the area (close enough to be within SAM range of the islands, but far away enough as to not appear intimidating to others) which would be able to protect them as effectively as SAM batteries based on the islands.
That is a big part of the reason why China is in no rush to formally and permanently forward deploy missiles to the islands - there is no real need, and China's interests are far better served holding those cards in reserve and as bargaining chips.
After all, China can deploy defensive forces to the islands pretty much any time it wants, even after the start of overt hostilities. However, deploying those assets prematurely would force a reaction from others that they might not really want to make.
Subtlety, patience and game theory are massive components of Chinese strategy. Despite all the western stereotyping about China needing to 'save face', its actually western politicians who are far more obsesses with 'optics' and how things appear in the media, whereas the Chinese are far more interests in results.
As far as China is concerned, the west can have all the media applause and tough sound bites, so long as China gets what it wants, it is more than happy to let the west put whatever spin they want to sell the story.