Questions regarding the operating temperature of 904 material; seeking answers from experts

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Regarding corrosion resistance in the introduction to 904L stainless steel, it is stated that due to its very low carbon content (up to 0.020%), no carbides form under normal heat treatment and welding conditions. This eliminates the risk of intergranular corrosion that occurs after conventional heat treatment and welding. Due to its high content of chromium, nickel, and molybdenum, as well as the addition of copper, 904L can be passivated even in reducing environments such as sulfuric acid and formic acid. Its high nickel content results in a low corrosion rate even when it is in an active state. In pure sulfuric acid within a concentration range of 0–98%, the operating temperature for 904L can reach up to 40 degrees Celsius. 904L (00Cr20Ni25Mo4.5Cu) is a low-carbon, high-nickel, molybdenum-containing austenitic stainless acid-resistant steel; it is a proprietary material developed by the French company H•S. It exhibits excellent activation-passivation transition capabilities, as well as very good corrosion resistance. It shows good resistance to corrosion in non-oxidizing acids such as sulfuric acid, acetic acid, formic acid, and phosphoric acid. It also possesses good pitting resistance in neutral chloride-containing media, along with excellent resistance to crevice corrosion and stress corrosion. It is suitable for sulfuric acids of various concentrations at temperatures below 70°C. It also exhibits excellent corrosion resistance at normal pressure in acetic acid and formic acid of any concentration and at any temperature, as well as in mixtures of acetic acid and formic acid. How do you understand these two sentences? Is the maximum operating temperature 40, or can it be used at temperatures below 70? Is the difference between the two related to different operating conditions? If so, please let me know the specific operating conditions!