World Partition region loaded but actors remain unloaded

I’m running into a strange problem with World Partition. I was happily editing my level as I have been, but somehow everything has disappeared except for the landscape and a few select actors. Everything is still there when I run it, either PIE or as a separate window.

The region is loaded in world partition

And yet, it all shows as unloaded in the outliner

I’m probably missing a simple setting somewhere but I’ve been through all of the filters and display options and can’t find anything helpful. I’ve unloaded the region and reloaded it to no change.

I can select everything in the outliner and select ‘Force Load’ and everything displays,

but I can’t seem to find any other way, it’s as if the region is loading, yet not recognizing the actors as being in that region.