I had a random epiphany when thinking about hypothetically, if Sora is revealed as the last DLC character. Again, this is completely hypothetical and I don't think it has anything to do with his chances, I just think that if it DOES end up being the case, it'd be hilarious.
Counting the Aegis sisters as separate characters, and also including Piranha Plant as one of the DLC characters despite not being a part of any of the fighter passes, if Sora is confirmed as the final DLC character, that would make him the 13th overall DLC character in Ultimate. And what version update would he consequently be included in as a result? 13.0.
Again, this is all completely hypothetical and I don't think such thematics affect his chances, but I still think that it's a funny idea.
But I'm really not betting on it.