H1 stamping and H4 interview both put under AP for no clear reason, Can H1 use drop box now if eligible?

My sister in law and brother in law went for their interview today. My BIL lives and works in the US on H1 and has been through several stampings. He was due for a stamping and this was her first interview for H4 (they just got married last week) so he decided to do it together. The consulate office put both their visas on administrative processing, gave them a slip for sending some documents and said the wait time can be any where from 2-4 weeks or more.

Now my SIL can stay in India for longer waiting for a verdict if needed but my BIL has to go back to his job and resume work. He is eligible for drop box, but can he use that now, since he did get his passport back today but his current application is in AP?

They told the officer they have their tickets booked for 9th Dec but that of course made no difference. Please advice.

Mr. Saurabh, are you still around answering questions?!