The human body is a remarkably adaptable machine. Even if years and years of neglect have allowed pound after pound of fat to fill out your frame, you can rid yourself of that lard at a much faster rate than you brought it on board. In that sense, time is your side! That you can gain muscle and lose fat is one of the reasons I stress to people not to follow the scale. Body composition and how you look in the mirror matters more than what the scale says. You could train hard and eat right and build five pounds of muscle and lose five pounds of fat, and what will the scale say?
That you still weigh the same. Frustrating, even though you've made good progress. Use the scale as a guide, but how you look in the mirror, how you feel, and how your clothes fit are much better indicators of your progress. If you're looking to lose fat, don't make huge calorie cuts. This will kick your body into starvation mode, reducing your metabolism and making it more difficult to burn off the fat. To prevent this metabolic slowdown and allow your body to burn fat at an optimal rate, make smaller calorie reductions every week or two. This is another way to outsmart your body and continue to lose body fat without lowering your metabolism.
