She should have AIS on at all times if unmoored unless it's a security concern so should assume it's still in position, however it has been sat there a long time with it on so why hide now.
CC the meliana has been there a few times but not for this length of time but I'm sceptical it's doing anything. Fueling cleaning I would expect via mobile tankers at quayside especially as there is a fuelling facility there but all the same still strange.
CC I've got no idea same as you just guess work could be as simple as direction ships are berthed as to location of transponders which my make it look like they're on top of each other. But whatever I know it's boring at the moment and has been a long time but this isn't worth getting excited about.