I haven't heard of anyone getting Walther to swap out that many. Most who have called S&W (Walrep), have been able to get them to swap out the two original non -A mags that came with their P22's.
My P22 came with the latest -A mags, so I did not personally need to swap out any.
I think your best bet is going to be to call S&W.
If you have not experienced problems using the old mags, my suggestion is to just keep using them.