Distinction between rule 6.8.1 and 6.8.4

[misra cpp]

In addition, we intend to clarify "explicitly designates" with the following example (or something similar):

int arr[10];
 
struct A {
  int m_a;
 
  const int &a() const { // compliant - the return expression references m_a, but does not designate it.
    return arr[m_a];
  }
};