SI50997 was superseded by SI52200
Let's suppose that SI50997 was flawed. And caused your system to hang and
disk to automatically reformat all drives in ASP 1, after posting your pay
scale at wikileaks, and all documents involving current litigation on
Facebook. Now, let's say IBM came out with a fix and called it SI52200.
You download it and apply it. SI52200 changes SI50997 from applied to
superceeded (by SI52200).
Now let me ask you, is that really a difference?