Houses move, and so does drywall!
Houses move. It’s a wild concept that you will hardly notice. But with all the weight and outside forces acting on a structure, it will move. Even if it is a quarter inch at a time. Most houses will be fine with these differences, but one area that tends to not fair so well is roofs.
On most houses the roof is separate from the drywall in any typical room. For this master bedroom, the tray ceiling is tied in with the roof. While the drywall tape was mostly well adhere, over time the tape became loose from what I can only imagine is house movement.
The answer for this, is to remove the tape where it has broken and replace with new. While a good taping mud is fine to use, a hot mud (which bonds and dries harder than normal mud) was used to give added insurance that it will not have the same issue anytime soon.
