I launched the T1 rocket from overworld, and select the moon as destination.
But when I landed there, it was Miranda which is a T5 planet, and dead from the radiation.
Rocket also cannot get back from the landed balloon.
I also found from the task book the Moon dim is shown as Miranda:
Not sure if this is a bug from the server side, and may related with the plugin.
Tested with client, and there's no issue with single player mode.