I have items with workflow being tracked on a PM tab. I've found that when a milestone is reached when the task is late or in the warning days period the staus color is retained.
My issue is that when a milestone is in the warning period (yellow color) and that task id for 100% completion if I reach the milestone (and complete the workflow) the color remains yellow. This bubbles up to higher tasks and indicates that an item is in the warning period even though it is complete.
I've been able to reproduce your results and have informed the PLM 360 Development Team.
Thank you for bringing this to our attention.