It still does not specify particularly that you can fly up to that temperature, just that the engine should perform without overheating. It also does not say you can not exceed 49C, just that the engine will not cool adequately. The other issue with that statement it does not quantify what atmospherics accompany that temperature, what if it was 49C at 10,000ft Elev, I doubt the engine would cool well then if it was still capable of high power.