Don't think you have any legal case.

A few years ago, a friend of mine jumped to a new job. But, the new company cancelled the offer for the position eliminated reason. He already notified his old company and could go back. He talked with a lawyer and was told he did not have a case although the company normally should not do that. The lawyer said it was just like you could accept an offer and did not go later. The company could not do anything to you although it was bad on your side.

Good lucky,

Xiong