Unable to Edit Parameter in Instance After Converting Back From Constant

Converting parameters into constants will remove the Instance's ability to change the parameter's values. But changing them back into parameters does not update in the instance editor and they can not be changed there.

Setup: Have a copy of content examples downloaded.

1. Open Content Examples
2. Navigate to the Material_Advanced Map
3. Find the Master Material and its first instance and double click on the materials for both.
4. Scroll over to the metallic parameters in the Master Material and convert both to constants. Click Apply.
5. Open the first instance's material to see the change.
6. Convert the constants back into parameters. Click Apply.
7. Go back to the first instance's material parameters.

Result: Converting constant back into a parameter does not update in the Instance's editor.

Expected Result: Converting constant back into a parameter updates in the Instance's editor.