According to this CCTV report, the Red Army from the Nanjing Military Region learned a hard lesson during the recent East Sea 17th Amphibious Exercise. A small Blue Army (professional bad guys) scout party was able to hold the much superior Red Army’s amphibious force at bay by calling for remote artillery support and by utilizing the massive fortifications to their advantages. The later Red Army attempt to out-flank the Blue Army's right by a tank encirclement was also countered.
The four hour stalemate was broken only after a Red Army helo inserted a detachment of infantry to knockout the Blue Army's artillery positions.
Amphibious operations are generally considered to be one of the most difficult and complex military operations. The OpForce the PLA would face would be better trained and equipped than their own Blue Force. A risky helo insert might not be possible during the heat of the battle or at a 140km distance. One must also assume that the PLA would not have complete air cover and that the OpForce would not be equipped with cheap MANPODS and AAAs.
You can watch the report (here)