2019.1 beta 4 broke SpeedTree v8 references

From the release notes:

That's all good, but as a result all external references to SpeedTree v8 got broken.

For example a ScriptableObject had a public GameObject field saved as:

Code (csharp):

1. modelObject: {fileID: 100000, guid: c54e42671c4cd8c4683ba3c1264db913, type: 3}

Previously (until beta 3) this pointed to the SpeedTree model.
Now it points to the CollisionObject0 inside the imported model...

If I reassign the property I'll get:

Code (csharp):

1. modelObject: {fileID: 100004, guid: c54e42671c4cd8c4683ba3c1264db913, type: 3}

Is this intended behaviour?
Do we need to reassign all assets references pointing to SpeedTree models?

 

Reported as a bug: (Case 1130496)