I agree, it would make more sense if they were specific in their degree requirement. At the same time though, your employer doesn't have a degree requirement for the hell of it. There's a reason for it, and while from your perspective it may not be readily obvious, it probably is from your...
So let me get this straight....You have an employer which has recognized your 4 years of good work enough to offer you a promotional opportunity. And, they want you to further your education as a condition of retaining that promotion? The bastards! Clearly, the thing to do in your case is...