go to options -> instance monitor tab and do update connection info for this server and just update it to point to the new server IP address
This would leave the information all in the same place in the GUI and you can have the license applied as it was.
The name displayed in DPA may be the same for this instance, so if you want to change the name, you can update a table named COND.
a. Select * from cond; -- the list of monitored instances
b. Update cond set name=’<new name>’ where id=<id>;
c. In about 20-30 seconds, the DPA home screen should show the new name.