2 months and 1/2 in such a little space!!! That's a confirmation : China's fleet is a coastal fleet (joke). More seriously, I would be surprised if, when this assessment is true, the picture above really presents the fleet that will sail.
Bohai Sea is about 150 miles wide and 200 miles from North to South, for a total area of 30,000 square miles, several times bigger than the Gulf of Lion. So it is not exactly a small area. More importantly, it is China's internal sea and it is safe from interference by foreign naval vessels.
If I remember correctly, both Chinese aircraft carriers Liaoning and Shandong did their first sea trials there.