Patent application must be in the form of mail application, and the date of patent application is the date of mailing postmark, right? (The fastest is the best)

You can apply electronically or in writing. Paper applications can be submitted directly to China National Intellectual Property Administration or the provincial authorities, namely the provincial bureau, with the date of receipt by the provincial bureau as the application date, or by express delivery or mailing, with the postmark date of mailing as the application date, and the express delivery with the date of receipt by the national bureau or the provincial bureau as the application date.