My book says 10k for everything except diesel and hybrid. For those the car tells you when to change. Mine says to change @5k, which I assume is sorta like changing break-in oil. Unless my driving style changes, next one after that isn't until 20k. This of course assumes you'll use the proper C30 spec oil and a Porsche approved filter.
There is an issue with this engine in VWs (and probably Audis) that's somehow related to the DPF that potentially but gradually contaminates the engine oil with diesel fuel. Perhaps the Porsche ECU monitors the contamination until it reaches an unacceptable level, then tells you to change the oil