A Rose for Emily - Point of View

The events of A Rose for Emily are a little hard to piece together because everything happens out of chronological order. This is probably due to the fact that the story is told in first person plural point of view. This point of view creates the effect that the story is told by the entire town. The events of the story happens in the order of the sporadic thoughts of the townspeople as the think of Miss Emily. From what I understand, Miss Emily has a family history of some sort of mental illness (old lady Wyatt). Miss Emily probably has some sort of mental illness as well because she denied her father even died, and she withdrew to her house when Homer disappeared. Additionally, Miss Emily most likely killed Homer with the arsenic then kept his dead body in her house in a locked room with the embroidered silverware and suit she bought for him. The room is described as: "A thin, acrid pall as of the tomb seemed to lie everywhere upon this room decked and furnished as for a bridal..." The word tomb gives away that there is a dead body in the room. One of the questions at the end says that Faulkner said that A Rose for Emily was a kind of "ghost story." This substantiated a thought I already had going. In the last sentence it says that they found an iron-gray hair on the pillow. The story says that her hair did not start turning that iron-gray color until sometime after Homer disappeared, and it says that the room where they found the body had not been opened in forty years. This makes me wonder: how could Miss Emily's iron-gray hair have gotten there if the room had not been opened in forty years and her hair was not the iron-gray color at the time she killed him?