User blog comment:B214/Volume 22 spoilers/@comment-1359322-20160722115757/@comment-27876048-20160722181002

When it comes to Xenovia, Asia and Ravel they wanted to be in Issei's peerage from the get-go so he technically already had his first peerage members he just lacked the rank. In my opinion I've always viewed that Rias and Ravel's mother were just "holding onto them" until Issei got his high-class promotion.