Steps to repro:
1. Open the attached project and "ProgressiveLightmappingExample" scene;
2. In the Context menu select Lighting>Day and let it bake;
3. In the context menu select Lighting>Night;
4. As soon as the lighting in the Scene view changes, in the context menu select Lighting>Dusk;
5. As soon as the lighting in the Scene view changes, in the context menu select Lighting>Day;
6. Let the scene GI bake;
7. Observe the light probe gizmos in the Scene view.

Expected result:
Light probes color is corresponding to the scene lighting setup (white).

Actual result:
Light probes are completely black (see attached video and screenshot).

Notes:
- The issue is not always reproducible, as it seems to be timing-related. To increase the repro rate try following:
- Switching light setups more times during the bake;
- Switching the light setups with different intervals (more or less often);
- Disabling auto-mode in the Lighting window, clearing the baked data, restarting Editor and repeating the initial steps.
- After step 2 disable the auto mode in the Lighting window, then do step 3 and enable auto mode again. After that follow the initial repro steps.

- Reproducible in Versions 2021.1.0b1, 2020.2.1f1, 2020.1.17f1, 2019.4.17f1, 2018.4.30f1;
- Reproducible on Windows;
- Reproducible only with CPU Lightmapper; not reproducible with GPU Lightmapper or Enlighten;
- Happens only on the Editor, not reproducible in the Standalone Player.