Right, the date of rank will ALWAYS be the date on the form you submit. That doesn't mean your TIG starts over at that date & all before is lost. If they've been gone less than two years & will pay the difference, then the date of rank is adjusted & all that time is counted for them. If they've been gone longer than two years, than they get a new date of rank to show when this service period started, but they still get credit for any previous service period in grade.