什么时候可以递交824表让家庭团聚呢? - same time when you file you

or any time after you file your I-485. I-824 is based on an approved petition, I140 here. if your I-485 approved, make a copy of your green card and send it to national visa center. They should send the package to China for processing and then info your relative for interview. it generally takes a year.