I don't see Babolat discontinuing the PS line of racquets any time soon. They are selling too well for the company to just up and get rid of them. There might be some new technology updates as is common in the industry but I don't see the line going away.
Like Storm said, the AS(T) is really more of an update to the AeroPro Control model. Sure there are definite similarities between the AS and the PS but I also think that there are pretty different markets for the two.