This read-only TimeTicks object reports how much time has elapsed since the operational status of this xDSL interface last changed. An admin uses it to judge line stability: a large value means the line has held its current state a long time, while a small value indicates a recent flap. For example, a DSL line repeatedly showing a small cXdslLineTimeSinceLastChange value on every poll would indicate the line is flapping frequently rather than staying stably up or down.