Strip the car and then spray epoxy. Take your time doing the bondo and any other repair work and if you need to spray epoxy over some areas that have been worked again all you have to do is scuff the epoxy first. After you spray the primer/filler do all your sanding and get it straight. Then you can spray your top coat. You should have no problems with the time between the primer filler and top coats since you'll sand the primer/filler anyway. The only time problem you might run into would be if you were using a sealer over the primer. There usually is a time limit to spray the top coat if a sealer is used. If that time limit is exceeded you will normally have to scuff the sealer before top coating.
When all else fails check the "P" (product sheets) for all the info you'll need.