Mesh emitters are not obeying changes to r.DetailMode

Emitter modules that are set to the "High" detail mode are removed when changing the engine scalability settings to "low", but not replaced when setting them back to "Epic." The emitter is updated correctly in cascade, but not in world. Building or simulating the level updates the emitter to its correct settings.

1. Open or create a project with starter content.
2. Open P_Fire
3. Click on the two "Flames" modules and set their Detail Mode to "High."
4. Save the asset
5. Place P_Fire into the world.
6. Change the "Effect" section of the engine scalability settings to low (located in the settings menu of the editor toolbar)
7. Change the Effects settings back to Epic

Result:
Observe that the flames do not spawn when reverting the detail mode back to it's maximum.