Two 100 mile trail races in the past year? You are indeed in awesome shape!

You'll find that walking with a loaded pack entails some different body mechanics and a different approach to pace, but unless you drastically overload yourself and put yourself at risk of stress injuries, the switch over to hiking ought to be fairly smooth. Most of what you'll be learning will be adapting to performing all of life's little chores while staying on the trail multiple days (obtaining water, eating, sleeping, washing, setting up and breaking camp, etc.)