Actually, I think some of those programs assume you're coming in underprepared. My suggestion would be to stay ahead of the curve as long as your body is able to handle it. If you have to cut back some because your body can't handle the added elements of the program, then cut back as necessary. However, don't reduce your training just because someone who wrote a cookie cutter schedule expected people who were following it to begin less prepared than you are.
In short, you're ahead of the curve. Take advantage of that fact by staying ahead of the curve for as long as your body allows.