As someone training for a comp, yes, I know that.
All the OP said is that he wants to lose 10-15 pounds. I'm assuming he just wants to get lean, not contest lean.
For me, I don't understand how taking out dairy alone will help you lose weight. To me, it's the same concept as low carb or low fat diet; when you omit foods from your diet, you can end up consuming less calories.
What I was getting at is if he ends up eating more calories than he burns in a day, just without dairy of any kind, is he still going to lose weight?