请问Pjiang 老师，小白兔, 及其他有经验的大侠，绿卡和 Welcome Notice 都收到了，但是Approval Notice 始终没收到，尽管Online Status 显示 两周多前就寄出了。请问万一永远收不到，对各方面有影响吗？
在Online Status 中提到：“Please follow any instructions on the notice”。
请问 “any instructions” 是指什么。万分感谢！
Receipt Number: SRCXXXXXXXXXX
Application Type: I485, APPLICATION TO REGISTER PERMANENT RESIDENCE OR TO ADJUST STATUS
Current Status: Approval notice sent.
On May XX, 2008, we mailed you a notice that we have approved this I485 APPLICATION TO REGISTER PERMANENT RESIDENCE OR TO ADJUST STATUS. Please follow any instructions on the notice. If you move before you receive the notice, call customer service.
You can choose to receive automatic case status updates, which will be sent via email. Please click here to create an account online.
请问 Approval Notice 这个文件本身有多么重要吗？今后何时能用得上？还是只要收到绿卡，有没有Approval Notice 无所谓了。这么说，这个文件可有可无？
非常感谢您的回答！！