When a user splits a Terrain object that has Draw Instanced turn off, the Draw Instanced setting will become checked.

Repro Steps:
1. Install the 3.0.1 Terrain Tools Package
2. Create a Terrain Object in the scene
3. Observe the Terrain Settings, notice Draw Instanced is turned off
4. Open up the Terrain Toolbox window
5. Go to the Terrain Utilities Tab
6. Select your Terrain
7. Press the "Split" button
8. Select one of the split Terrains

Actual Results:
Draw Instanced is turned on

Expected Results:
Draw Instanced would remain turned off

Note:
This bug reproduces whether you have Keep Original Terrain checked on or off. It is checked on for the kept original Terrain as well as all of the new split terrains.