They already have the asnwser: of course it will. They are trying to find ways to mitigate it though. One way for example is NOT to offer rear seats AND wing delete. Only one or the other. Of course they won't offer a convertible either, which protects a lot of regular 991 sales especially after the initial batch of sales of coupe before the convertible becomes available (that's only when the convertible comes after the coupe).