Overlap trigger on Event Begin Play doesn't work after converting project from 4.7.6 to 4.8 P2

Overlap trigger on Event Begin Play doesn't work after converting project from 4.7.6 to 4.8 P2.

The user thought this was related to using Custom collision object types but it is reproducible with the default types as well.

1. (In 4.7.6) Open a new Blank bp project with starter content
2. Create a new bp actor class named 'bpOverlap' & open it
3. In the Components tab > Add a StaticMesh component
4. In the Details panel of the StaticMesh > Static Mesh > Add a 'Shape_Sphere'
5. Collision > Set the 'Collision Preset' to 'Custom'
6. Set 'Object Type' to 'World Dynamic'
7. Set all 'Collision Responses' to 'Overlap' (see screenshot #01)
8. In the Event Graph > Create the bp from screenshot #02 (On begin overlap change the material)
9. Compile & save
10. Open the Level bp
11. Create the bp from screenshot #03 (Spawn 2 of the 'bpOverlap' blueprints in the same location)
12. Save & PIE
13. The bp is spawned twice and they will overlap then trigger the material change
14. Save project & close
15. Convert this project to 4.8 Preview 2 (or later if available)
16. Once opened > PIE

Results: The overlap event will not be triggered on Event Begin Play

Expected: For the overlap event to be triggered like in 4.7.6

Note: If the above setup is created in 4.8 Preview 2 from scratch, it will work. Only converted projects seem effected.