That is bad reporting. SpaceX always planned to burn the 2nd stage until it ran out of fuel. Elon always said they weren't sure exactly what the final traject

That is bad reporting. SpaceX always planned to burn the 2nd stage until it ran out of fuel. Elon always said they weren't sure exactly what the final trajectory was, just that the roadster would be sent out as far as possible. They weren't sure how much O2 would boil off during the 6-hour coast after launch before it departed orbit. That was part of the test. Also, they weren't heading towards mars - just outwards towards mars orbit. When the roadster crosses mars orbit mars itself will not be nearby. If they wanted to actually reach mars they would have had to launch during a specific launch window when earth and mars lined up at the correct angle. This happens once every couple of years.