public void unrelateAcrossR689From(Value_c target, boolean notifyChanges) {
    if (target == null) return;

    if (WritesValue == null) return; // already unrelated

    if (target != WritesValue) {
      Exception e = new Exception();
      e.fillInStackTrace();
      CorePlugin.logError("Tried to unrelate from non-related instance across R689", e);
      return;
    }

    if (target != null) {
      target.clearBackPointerR689To(this);
    }

    if (WritesValue != null) {

      m_l_value_id = WritesValue.getValue_id();
      WritesValue = null;
      target.removeRef();
    }
  }