Assuming it kept the same mass. If it had a lot more mass, the Earth's orbit would be identical to it's orbit around a star with that much more mass. The fact

Assuming it kept the same mass. If it had a lot more mass, the Earth's orbit would be identical to it's orbit around a star with that much more mass. The fact that an object is a black hole only becomes relevant when something passes the event horizon. Outside the event horizon, it acts like any other object with the same mass.