Now to update a station,
We delete it and create it again,
this lead to two command with same argument.

Is able to use a new command to do that at once.

What do you mean with "update"?
Move the station to the player's current position?

@Phiwa Yes, for example I set station at mountain "A",
and wish to move it to mountain "B".

The current process is delete the station at mountain "A"
and create a same name station at mountain "B".

A simple process is I just stand at mountain "B" and execute /dt updatestation stationName,
then the next time someone travel to "stationName", he will go to mountain "B" instead of "A".

Sounds like a good idea.
Command should be
/dt station move <name>
or
/dt station update <name>