Yes blue split for white. She's showing a white flight feather, and possibly a white spot on chin too.. those are normal for blue split for whites.
Pieds show white on anywhere else.. back of neck, higher up on the wings, back or on the tail.
One very confusing issue is the fact that pure pieds can look like blue split whites- pure pieds look blue with a little white on the wings/chin.. but some will also show a little white elsewhere.. I had one pure pied that had a single white tail feather.
The pieds with patches and streaks of white basically are "1/2 pied 1/2 white' genetically.
However since we know the parentage of your birds- India Blue x White, no need to guess if they are split white or pure pieds..