[jdiwnab]

Move component and, sometimes even dragging, move pieces without regard to constraints. Their position is saved, but dragging and updating constraints (like adding a new one, or adjusting an existing one or just hitting update) will cause all pieces to return to the constrained configuration. It might put some of the pieces back in a slightly different place than where you had them, but Inventor is just following the constraints. If there are any degrees of freedom, your part could be anywhere along that line (or rotation) when you update it and will most likely be closest to the position that it was in when it was rearranged. If you like the way it is now, try to constrain it that way so that it is not a concern to update constraints.