The RWY designator change is definitely because of the chance of confusion as the new Western RWY takes form. The SMC split? Not too sure of the advantages of this one at the moment. Where the division will be will still leave most of the radio chatter on the northern "domestic" frequency, even more so when the new RWY is commissioned (unless there is a further split planned?) What is left on SMC-South won't be much. Wonder if the same controller will work both frequencies? Can't see that being much fun on a busy day!