This trait buff is gonna do so much for this character.
To explain the rules of holding trait, you cannot release trait during block stun or hit stun, if you do so the trait won't come out. If you can't move then that means no trait release.
This applies to knockdowns and juggles, you cannot release it during a juggle, and you can't release it while coming off the ground until you can move again, not including back/forward dashes. So the frame you wakeup it seems like you are able to release it, but if you wakeup with a dash you still haven't been reset as standing so you can't release trait until the recovery of the dash is over. Same idea with tech rolls, air escapes and throw/throw techs.