How long does it usually take for a lawyer's letter to arrive?

Legal analysis: it depends on the speed of express delivery. A lawyer's letter refers to a professional legal document made and issued by a lawyer to disclose and evaluate relevant facts or legal issues, and then make a request to achieve a certain effect. There are two levels of legal relationship, one is the authorized relationship between lawyer and client, and this level is the core legal relationship. The second is the legal relationship between lawyers and clients. A lawyer's letter shall, according to the reasonable requirements of the client, give a notice to the other party or explain the reasons to the client within an appropriate scope, so that the client can make a decision. There is no necessary connection between receiving a lawyer's letter and being sued. Receiving a letter from a lawyer does not mean that you will be prosecuted. It depends on the other party's decision. After receiving the infringement warning letter or complaint from the patentee, the parties concerned should first take it seriously and then carefully distinguish it. If you don't do it yourself, you can reply and explain, but you must have corresponding evidence. If you do it yourself, you should carefully analyze whether the infringement is established.

Legal basis: Article 188 of the Civil Code of People's Republic of China (PRC) requests the people's court to protect civil rights for three years. Where there are other provisions in the law, those provisions shall prevail. The limitation period of action shall be counted from the date when the creditor knows or should know that the right is damaged and the debtor knows it. Where there are other provisions in the law, those provisions shall prevail. However, the people's court shall not protect the rights that have been damaged for more than 20 years. Under special circumstances, the people's court may decide to extend the time according to the application of the obligee.