Light Probes - dynamic conditions

Hi there,

i know i can create a partially dynamic atmosphere (shadow/lightning) with light probes. Therefore a lightmap will be baked. What if i have an object (e.g. a big rock), which has a shadow and this rock gets removed (gameplay: an object "eats" it). The lightmap will still through this shadow.

What's the best solution (or maybe the sole)? Could i create another lightmap where this object doesnt through a shadow and i change the lightmap at runtime? But how big is one lightmap. E.g. i have up to 10 objects, which can be "eaten" and i need to carry 10 lightmaps (on mobile plattforms!)

Many thanks, Thomas