How do I set the plan to forecast all items starting at level 2?

Summary:

I am trying to set the forecast generation to only forecast items at level 2, across my entire business. I have set the "MinForecastLevel=2" in my override parameters. However, after the plan is run, I still see many items (about 50%) which have a Bookings Forecast Level = 1, and many more that are null.

Re-creating the demand plan to remove level 1 is not an option in my environment due to complex integrations.

1. Did I enter the override parameter correctly?
2. Do I need to set the items to forecast at level 2 manually? I do not see a seeded measure to do so.
   

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