This bug erases all the mesh data if mesh is used as instance in Hierarchical Instanced Static Mesh Component. Mesh data is completely removed after editor restart. Repro steps: Create a blueprint, place it in scene and in Construction Script add ‘Add Hierarchical Instanced Static Mesh Component’…

Same , I was able to trace StaticMesh->RenderData->LODResources is an empty array, and I got a ton of “Failed to generate distance field data due to missing LODResource for LOD 0.” log message