If I save the attribute from Classic and open it in Modern User Experience (UX) it shows, but if I try to change it will show no results again.
STEPS TO REPRODUCE:
Expected Results: status Report “Current Phase” shows parent tasks from the project task list
Actual Results: No values are available under 'Current Phase'. If you save the attribute from Classic and open it in Modern UX it shows, but if you try to change it will show no results again.
Release : All Supported
This was reviewed as DE59617 and determined to be not a bug (NAB)
The design of the Current Phase lookup will only display "Phases". and not tasks (nor milestones). A phase is something at topmost level and has a grouping of tasks underneath.
In summary, the field will display all tasks that have a subtask on it