Static Lighting from a nested Blueprint is not saved in Lighting Build

Licensee has a setup in which static lighting is placed in a Blueprint Actor and then a New Blueprint is created with the parent added to this new blueprint. All Elements in both Blueprints are set to a Static Mobility. When you Build lights and PIE, the lights seem to be built correctly. Until you restart the project in which case all lights in Child Blueprint are marked dirty and must be rebuilt.

Workaround: Using an actual Child Blueprint instead of nesting one blueprint inside another will result in no issue.

QUICK REPRODUCTION:

1. Open attached UDN_SpotlightBP Project
2. Build Lighting
3. PIE
4. Close Project
5. Restart Project
6. PIE

RESULTS: No Lighting Needs to be rebuild on first PIE, but on restart Lighting does need to be rebuilt on PIE

EXPECTED: Lighting should not have to be rebuilt if nothing changes and the editor is merely closed and reopened.

FULL REPRODUCTION:

1. Open a Blank Project with no Starter Content
2. Create a New Blank Level
3. Add a Cube Basic Shape to the level
4. Create a New Actor Blueprint
5. In the Actor Blueprint, Add a Static Spotlight as a component
6. Save and Compile Blueprint
7. Create a New Actor Blueprint
8. In the New Actor Blueprint, add the originally created Blueprint to it.
9. Save and Compile New Actor Blueprint
10. Place the New Actor Blueprint in the Level such that it illuminates the Cube.
11. Build Lighting
    #PIE
12. Close Project
13. Reopen Project
14. PIE

RESULTS: No Lighting Needs to be rebuild on first PIE, but on restart Lighting does need to be rebuilt on PIE

EXPECTED: Lighting should not have to be rebuilt if nothing changes and the editor is merely closed and reopened.