what does this warning mean?

[ntnik]

""Wall and instance have different phasing settings. Automatic creation of the infilling wall fails.""

i am following someone else's work setting up existing, demo, new views....the model seems to be set up pretty well regarding existing and new components.....i got this warning a few times, most recently when i raised a wall in elevation a little higher to meet the roof.....i haven't noticed anything to be concerned with (yet) as a result of the warning....just wanted to know if anyone could explain this to me for fear of discovering a surprise down the road

[cdatechguy]

If your modifying a wall, be sure the view your in relates to the phase that wall or any other object is in as well. Such as if your modifying an existing wall the view your in should be existing. If you make changes to an existing wall in a demo or new construction it will think your making changes to the existing wall.