The DHS Secretary announcement reflects that the two-year EAD is issued to those I-485 applicants "if their I-485 applications are expected to be pending for more than a year." The question remains how they would determine it. Among others, two questions may be relevant here.
The first question is the point of time of determination of "expected to be pending more than a year." The second question involves the basis of the determination of "pending more than a year." As for the first questions, there can be two different points of time: At the time of "filing" of I-765 application or at the time of "adjudication" of I-765.
Since it is the USCIS that will determine whether to issue one-year or two-year EAD based on these standards rather than at the request of the applicants, the agency is likely to determine the eligibility of two-year EAD based on the situation at the time of filing or at the time of adjudication. Generally, the USCIS has been adopting "filing date" rather than "adjudication date" for similar situations. We hope that the agency takes a similar practice in the two-year EAD eligibility determination point of time.
As for the second question, the basis of determination of "expected one-year pending" can come from the visa number retrogression in the Visa Bulletin or the agency's backlogs in I-485 processing.
People will remember that the USCIS has already changed its EAD regulation allowing the USCIS to issue an EAD for more than one year. However, implementation of this revised rule has been deferred or delayed until now.
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