The Overall Status field in Modern UX (MUX), despite the returned value is "null" it is shown as "On Track" on tiles and report page.
1. On the Status Report page of the project leave empty the status fields Schedule status (cop_schedule_status), Scope status (cop_scope_status) and Cost and effort status (cop_cost_eft_status)
2. According to calculation of the empty values, the Overall Status = Null and I would expect that it would show the default color of "white", but instead it states it's "On Track" by default.
This is working as expected. By default in the MUX it's assumed by default that a Status Report is "On Track", if the calculation of the Status Report is Null. This works differently than the Classic UI.
Release : 16.0.1, 16.0.2
The root cause of this issue is similar to the reasoning documented in this document: