ΔE 11.4, fair: the same colour family, but not a straight swap. Casandora Yellow is a little darker, more muted than Light Rust. They are different kinds of paint: AMMO by Mig Light Rust is an opaque base/layer paint and Citadel Casandora Yellow is a wash/shade, so they won’t behave the same on the model even where the colour is close.
Only where an exact match doesn’t matter, such as a new unit or a highlight. Fair match (ΔE 11). Casandora Yellow is a little darker, more muted than Light Rust. They are different kinds of paint.
The same difference applies the other way round: Light Rust is a little lighter, more saturated.
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 Light Rust on the colour wheel See Casandora Yellow on the colour wheel
All matches: Light Rust equivalents · Casandora Yellow equivalents