It seems more complicated than it really is.
India Blue birds are one species.
Green birds are separate species (I get confused as to status of greens, there are green experts here, I'm not.)
Crosses between IB birds and green birds are spaldings, and vary in appearance depending on how much green blood.
IB birds have different pattern mutations (white, pied, blackshoulder) and different color mutations (purple, midnight, peach).
To "name" a bird, you name first its color, then its pattern(s), and you indicate if it is a spalding. The UPA has a list of varieties which basically works through the possible combinations for the known colors and patterns. White is a pattern but sometimes treated as a color for naming purposes. White conceals all the other colors and patterns.
Make sense?