Thank you for your many suggestions and advices, the interview went smoothly!!! My dad got his green card from GuangZhou US consuluate and landed US through NYC (we are living at different city along the east coast) at the end of August!!!
I wonder how long it will take my dad to get the official green card
-About one month to two months. USCIS will send the card to your father directly and you do not need to do anything.
even though his immigrant visa serves as his tempoary green card for one year starting from the date of his green card approval.
Whom should we contact regarding this matter?
-USCIS. If you can not receive the card in two months, just contact USCIS. See:
and where he will get this new green card from? Vermont or local immigration office?