Lightmass Importance Volumes overridden / cleared out / deleted in Hidden Levels

Is there a way to retain the probe data inside of Lightmass Importance Volumes even when their corresponding levels are hidden during bake?

Our use case:
We have a large building with dozens of interior rooms. Baking takes quite awhile, and is typically done by only one or two team members. So we have rooms broken up by sublevels (recommended by the thread here: Separate lighting between streamed levels - Rendering - Unreal Engine Forums)

By example, when we need to update lighting in Rooms 3 and 7:

  1. Hide all sublevels except for Room 3.
  2. Build Lighting.
  3. Hide Room 3, and Show Room 7.
  4. Build Lighting.

The Result: probes inside of any Lightmass Importance volumes inside Room 3 are cleared.

Is there a way to retain them? If not, can anyone share a production-proven approach to “properly” bake lighting in a scenario like this one? Thanks in advance!

We are having the same issue. Does anyone know if this is a bug, or was this feature taken away?

It’s already been reported here: Hidden Levels Rebuilding in 4.14 - World Creation - Epic Developer Community Forums