If you google 'Luconia Shoals' news, there are a lot of them recently, so the rumors are pretty much confirmed. Regarding that 'anchored for 2 years', I think you are right, it is easier to swap the ships. Regarding SCS disputes, Malaysia tried to be on the good side of China so it probably tried to down play the Chinese Coast Guard ship(s) in the vicinity of Luconia Shoals until now the Chinese engineers started to conduct land survey on the Luconia Breakers.
Here is one from Borneo Post:
Photo shows the China Coast Guard vessel, which has been anchored in Gugusan Beting Patinggi Ali for about two years.