According to analyst Ming-Chi Kuo, Apple's suppliers anticipate a rise in demand for the iPhone 14 series in China. Kuo suggests one possible explanation: Apple is benefiting from Huawei's compelled exit from the 5G industry. This resulted in little competition for Apple as the leading player in China's high-end market.
The plain iPhone 13 was the top-selling individual model in China in January, as it was in October and December as well. The iPhone 13 series has been quite successful overall - more successful than prior generations, which would make the increased demand for the iPhone 14 all the more impressive. It alone sold 2.3 million of Apple's total 5.1 million units for the month.
There are many local Chinese brands that sell high-end 5G phones, including Honor, which has been supplanting Huawei in some markets. However, it appears that none of the local (or international) businesses have been able to establish themselves as the top premium brand, as Huawei previously did and Apple is currently doing.