Lightmap static objects are no longer lit by light probes. This is the case since Unity 5.4. In Unity 5.3, lightmap static objects could be lit by light probes.

Steps for reproduction:
1) Create a new scene and a lightmap static cube object
2) Create a light probe group
3) Open the Mesh Renderer component in inspector
4) Observe that `Light Probes` option in Mesh Renderer component is locked and can not be changed

Workaround solution for users who want to address this issue:
- It is possible to override `Light Probes` option in Mesh Renderer component through `Renderer.lightProbeUsage`.
Find the details about this API call here: https://docs.unity3d.com/ScriptReference/Renderer-lightProbeUsage.html

- Alternatively, you can just untick static, select the appropriate light probes usage and tick static again.