It looks like the two ships might be having a conversation.
Shandong: "Hey you, what are you doing here? This is my dock. Your dock is on the other side of the harbor. That spot is for my buddy 89."
Type 055: "Not like I have a choice, they sent me here. Its not like I'm staying here forever. I will be leaving for trials soon."
What's on the dock right now is quite important. It is obviously a large commercial ship. A very large one. But most importantly, they are not reserving this dock just for the maintenance of the two carriers. They are not planning any maintenance of the two carriers that would require the dock anytime soon, and if there is such an issue, they would have to use a commercial dock, which may have the space but not the equipment and personnel. The Shandong returning to Dalian might be all about minor issues, needing to adjust or replace something.