User blog comment:B214/Azazel Cup discussion center/@comment-6341273-20170324021932/@comment-10330822-20170324143641

Still he might have "vented" on the army a little bit. The fact that Loki and the UL already knew the army wasn't going to win against him, and yet, they were still shocked when he showed up "earlier" than expacted, kind of shows that Issei must have put in some real work for him to go back in time so soon.