Using scenario editor, I created a town near waters and put an oil rig in waters.
When I try to delete town, now it refuses that it has station or objects using city name. It do not let me delete oil rig also in any way. I renamed oil rig also to give it separate name from city name it inherited but no success.
I have many other towns and industries in the scenario so starting a new scenario is not the best option.
Let me know if I can just delete couple of towns with oil rigs.