Yeah, something very odd is going on.
Jim has hardly been consistent about Drakul and the Black Court either, and I personally don't put it down to Jim having multiple realities going on.
I believe Jim has had multiple ideas about the Black Court and Drakul, but has forgotten which idea he has used or is going to go with (and perhaps even confused himself - he says he relies on the Dresden wiki but that thing is full of errors and conjecture).
For instance, we first learn about Drakul in Blood Rites from Ebenezar. Eb mentions him when discussing the relationship he and Kincaid have. Eb says that Drakul is a scion and that Kincaid is one too, and explains how scions work. However, in an interview when Jim is asked about what Drakul is a scion of Jim says that Drakul ISN'T a scion of anything. He seemingly changes his origins/backstory. Jim goes on to say that Drakul is something "entirely inhuman" that got trapped in a mortal/human body.
Another example is that when we first learn about the Black Court (I forget which book, probably Grave PerilBlood Rites) we are told (by Harry I think) that the Black Court have been preying on humanity since the dawn of humankind. I believe that Eb tells us that Dracula ran off to join the Black Court as a teenage rebellion. But in an interview, Jim contradicts this seemingly and tells us that Dracula rebelled against Drakul and wound up turning himself into the FIRST Black Court vampire in order to impress Drakul but it didn't work out so well.
So, is Drakul a scion or not? Is Dracula (his son) the first Blampire or did he just join the team?
Up until Battle Ground there hasn't been really anyway to resolve this. And while we can't outright resolve either of those questions, I think there are some hints and possible solutions.
My guess is that Jim has always planned on Drakul being a starborn. But he didn't want to go into all that years ago (considering that we are only learning about some of it now) and so he sort-of gave us half-answers, perhaps to muddy the waters and perhaps because he was trying very hard to give nothing away and gave us confusing answers.
Because he doesn't want to give the game away about Harry's starborn (and perhaps Destroyer) nature, he can't afford to give away too much Drakul information either (given that Drakul is starborn also). Perhaps it comes down to concepts. Perhaps starborns are not exactly scions in the traditional definition Jim gives us. But maybe they sort of are as well. One thing Jim has been hinting at and layering in the series is the idea of bloodlines. And somehow, I think it ties in to this. It could be that starborns are a sort of quantum locked creature (we know Jim loves his Schrodinger) that both IS and ISN'T it's true self until a Choice is made. Scions are effectively like that to a point. And the whole not-throwaway line Mab says to Harry about remembering that Immortality is no substitute for intelligence, should that ever become necessary to remember. I suspect that's part of the Choice for starborns. Become Immortal and gain all the power that comes with it...but perhaps lose crucial perspective and choice, and therefore in some ways, intelligence/knowledge. Knowledge that is unique to being mortal. The fact that she quickly says the second part of the sentence before Eb can speak, and he is clearly annoyed she says that to Dresden in particular, tells me that she was giving Dresden knowledge that perhaps she normally couldn't. She is just as bound, in some areas, as the Mother's are.
As for Dracula and the Black Court, my take is a simple one: the idea changed and Jim did a soft retcon. Initially, they were an old race of monsters. But perhaps Jim then decided it would be more interesting if they were a relatively new power that gained A LOT of power very quickly. It seems the "Elders" are not all that much older than Mavra considering even though she was the least of them, she was included in the bunch.
This idea that the Black Court are new, and that there are certain similarities between the various Vampire Courts and the fact that they all seem to be under the banner of Vampires (and seem even to work together...in the same way the Fae work together when faced with collective issue), spawned a whole series of theories about how Drakul may have been the progenitor of all the Courts and each time he seems to be trying something new in order to further his goals. This gains more credence considering Listens-to-Winds comment about Drakul having his goals beyond what was going on in Battle Ground.
I wonder if it's not Drakul creating all these courts exactly, but whatever being he simply is a facet of. That whole thing about Vadderung being a facet of the greater being, plus the thing about how Cornerhounds are actually just the avatars of a being from "beyond", makes me consider that perhaps the being we encounter in Battle Ground called Drakul is only a part of the greater being. Perhaps a greater part, or even THE greater part, but nonetheless a part of the whole. Also, the way that ALL vampires seem to spread their power between the whole group. The power of the blood. And blood/life force feeding is a central theme to all of them.
And perhaps, Harry will have the choice to become a part of the greater being that he a "scion" of. I say scion, but I more mean that his unique circumstances due to his bloodline and birth connect him to. Strangely, he seems very similar to Vadderung (the shared lightening motif combined with a sort of dark energy).
Hopefully, Jim will give some definitive answers around all this (like he has around Mab's strength relative to Archangels or Nemesis' ability to infect mortals).