After 10+ hours since your last insulin response all the mitochondria in your body will have switched over to burning fatty-acids instead of glucose. Any time after that would be a great time to liberate fatty-acids from adipose through exercise.
From my own experience I just focused on the fasting for the first month, by all means do simple cardio for 30-45 mins, then once you’re used to the feelings first thing in the morning start out a basic dumbbells, kettlebell workout alternating with some cardio and Tabata workouts.
I walk in the morning fasted, then in the afternoon after my last meal.
If I were doing anything more than light exercise, I would do so before a meal.
But really, exercise when it’s convenient for you.