I don't have any inside info, but the same thing happened to me last year: Complete in October, then got a letter in November saying my app was on hold. I didn't hear anything else from them until April/May when they sent me a letter saying the class was full.
If DMU is your top choice, I'd call the admissions office to tell them that, say you're disappointed your app is on hold, and ask if there's anything that might make them look at you again. Because from my experience, I'd say if they put you on hold and you don't get in touch with them, they'll just leave you on the bottom of the pile.