Transform does not update after first time for Instance Static mesh in Blueprint Editor

In 4.15 When you update the transform of an instance static mesh a second time the editor does not update the location, to get the update to display correctly you must close and re-open the blueprint. It will transform correctly the first time.

Regression:
This issue does not occur in Binary version 4.14.3 (CL 3249277)

1. Create a new blank project with Starter content
2. Create a new actor class blueprint > Name "Test_BP" > Open Test_BP
3. add an InstancedStaticMesh component
4. Under Details panel Set Static mesh to Shape_Cube
5. Under the Details Panel Under Instances, Add 1 unit to the array
6. In the new array member open the transform menu
7. update the value of X to 500 (Expected result)
8. change the value of X back to 0
   Results: The mesh does not update its position in the blueprint editor
   Expected Result: The Mesh updates its posistion