ΔE 15.5, loose: different enough that you should pick on purpose. Iceborn is a little darker, much more saturated than White Precision Base.
Not as a straight swap; see the closer alternatives below. Loose match (ΔE 16). Iceborn is a little darker, much more saturated than White Precision Base.
The same difference applies the other way round: White Precision Base is a little lighter, much more muted.
ΔE is the colour difference between our two swatch estimates: under about 6 is close, over about 15 is loose. Real paints also differ in finish, coverage and how they thin, so test before you commit.
See White Precision Base on the colour wheel See Iceborn on the colour wheel
All matches: White Precision Base equivalents · Iceborn equivalents