That happened to me. My instructor honored ALL of his student's paid lessons. He wanted to KEEP his students and we all followed him to a new location. The only thing we were out was the hourly dance floor fees to the new studio. I think it was only a few of his competitive students who had 20 or so lessons paid up. When your taking 3 or 4 times a week those go fast. Most had way fewer than that.
I would think a good instructor would do this than try to start from scratch somewhere else.
I guess I would go in and take as many of those lessons each week as possible. Then I would ask your instructor would honor any left over lesson so you could follow him to a new location.