Depending on if you are using surface cache or hit lighting mode, it will either pre-compute “cards” that represent a material for use in raytracing or it will evaluate the material pro. You can view them with the visualization viewmodes. Until the cards are re-computed, dynamic material changes won’t be reflected in GI or reflections. This can also cause issues with materials that rely on view vectors, like fresnel.
Hit lighting evaluates the actual material. So it can handle real time changes and other more complex materials, but at an added cost.