User blog comment:Mich, Michele & Kuhla/Guide: UBB and the OD gauge/@comment-68.98.29.49-20150314204943

Are you sure on the unlocking UBB for older unit? I've seen that it is just get SBB lv10 like the newer ones. Are you confusing UBB with the Extra Skill? Older units' 7 star forms requires their own specific sphere to get their extra skills.