I also had a similar problem so rather than creating a new thread I'll post here too, if that's alright?
Guildcard: 42161321
Character: Slot 1
Date/Time: 9:15 Eastern 12/15/2015
Description: My mag was a Garuda while I was leveling it with my HUnewearl then when I joined my friend it went back to Kaitabha with levels in DEF as well.
Comments: I quit in Ruins 2 instead of Pioneer 2 if that helps figure out the bug.