So, this is the pertinent section of the tiering FAQ
The question is How can a character be 1-A and above without an infinite-dimensional/infinitely-layered cosmology, then?
My hesitation is that, the crux of the issue is whether or not layers could be added, infinitely so, without it ever affecting the Overvoid. I understand that the wording says "by virtue of transcending [physical space] entirely" which is likely true of the Overvoid, but arguably is also true for other realms/layers of DC, so it's not enough to simply being a conceptual layer above space.
I don't think any of the evidence strongly supports the specific notion that any amount of layers could be added, which is the manner in which Overvoid could be 1-A despite not having an infinitely layered cosmology. So without strong and direct evidence of that, I don't think we can use this shortcut to 1-A, and the transduality doesn't really influence that IMO.