Semantic nomenclature ...
The "Hill Style" longbow is an
AFL - American Flat Longbow.
The "Flat" part means that although it contains many of the characteristics of the English longbow (ELB), it's missing the ELB's rounded belly, hence both an AFL's back and belly are flat.
The AFL limbs are either dead straight, or back set (reflex) or belly set ("string follow").
If a longbow combines back and belly set (r/d, or reflex/deflex), it's no longer a "Hill Style" AFL, it's now some flavor of a hybrid r/d longbow.
If a braced longbow has that classic AFL "D" shape, you may be surprised when it's unbraced and you see that the limbs are mildly snaked. Yup, ain't an AFL, it's longbow hybrid r/d.
Hope this helps a bit.