In the scene where Christiane is waiting for Bruno's phone call in her apartment, the doorstep onto the balcony is clearly visible. A few moments later when she rolls outside in her wheelchair it has been replaced with a ramp.
The first letter talking about the move to another grave of the brothers' grandmother says she has to be moved due to the construction of "Bundesstraße 17". Later the gravedigger says it's about "Bundesstraße 7"