So, I deleted my army last month and started over. That time, my global ranking was reduced by one-third and my personal ranking went from 100K to zero. I started over and progressed back up to diamond level winning the other chests along the way. I reached 100K this morning and repeated the process. This time, my global ranking again declined by one-third but my personal ranking remained at 100K despite the army delete warning pop-up saying that it would go to zero. I submitted a help ticket....we'll see what happens.