For some context, the Eastern Theater Command resides in the Jiangsu province and is responsible for the security of the Easter China Sea and Taiwan Strait. A better depiction of that territory can be seen below:
Considering recent China-Taiwan tensions, you can see why this is a particularly important area.
Anyway, Xi has made a visit to the command there and urged the military to deepen war and combat planning so as to increase the chances of victory in the event of an actual combat, according to China’s state media.
That is definitely some heavy posturing on their end.