回复：请问各位专家，I-824批准之后,应该做什么？何时能收到美国国家签证中心发出的三号包？

Once the I-824 is approved, the file will be transferred to the National Visa Center (NVC). The NVC will assign a case number. Then the Applicants will have to pay the immigrant visa fee bill. Once that is paid, the Applicants should submit their DS-230 (Immigrant Visa application) forms and their original documents. Once the NVC is satisfied that all the documents are in order, they will schedule the Applicants for an Immigrant Visa interview -- provided the Priority Date is current at the time. Then the file will be transferred from NVC to the US Consulate abroad.