依親綠卡收到notice of file transfer - 移民

大家好,
謝謝一直以來專業板友提供幫助,
本人今年8月中完成成年未婚子女依親綠卡面試.
面試官說沒問題的話兩周後綠卡會寄出.
但是後來收到一份” notice of file transfer for visa regressed cases”
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A final decision cannot be made on your case at this time because a visa
number is not currently available. This officer is transferring your pending
I485 to national benefits center. The office indicated below will retain
your case until the visa number becomes available and will ultimately conduct
the final processing of your case. This transfer will ensure better customer
service and faster case processing.
---
我的PD: 01/11/2016

請問對於這個通知,
想請教接下來的情況還有等待時間的建議.
謝謝大家!


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