Has a demon ever switched sides in the blood war?

Within the background of the blood war the Demon Graz’zt is presented as a former devil who switched alignments and joined the demon ranks.

Is there any example within the lore of DnD (from any edition) of a demon doing the equivalent? Switching sides to become a devil, is this possible in terms of what a demon is how it is formed and maintains its existence?

Just to clarify I am looking for an example of a powerful being, named character etc as opposed to a generic type of creature (for instance succubi)