I certainly hope they don't convert too many of the category 4 cabins. As those are the only non-CL cabins on the Magic that will sleep a family of five, converting very many of them would be an inconvenience to some guests.
If Disney does make this move, what do they do in a situation where a family has already booked a regular category 4 and that cabin is now going to be used for concierge level. I would guess Disney will require them to move, but that seems a little unkind to me.