H1B, H4 Visa

Hi All,
Here is what I am experiencing till today.

Location: Mumbai, India

Bio- 2nd May 2017
Interview - 3rd May 2017

Questions asked:
Interviewer: What is your job role?
Answer: **** **

Interviewer - Your I797 is expiring on 8th July, what are you doing here in India?
Ans: Came India on vacation to celebrate my USA born son's first birthday.

Interviewer - You work for which company?
Ans: I work for company B.

Interviewer - But in the system there is a different company.
Ans: Because my company B acquired company A. So the company name has been changed.
Note: After mentioning this I handed over company name change letter to interviewer which was provided by my HR along with the client letter. She took a look at that and then said wait for sometime. She went somewhere with that letter and came back after 5 min or so. and then said:

I - See, I cannot validate this document right now. We need some time for this.
Note: With that she handed over me 221 (G) blue slip with only one option checked "Your application requires Additional Administrative processing. The office will contact you via email". Then she asked:

I: Which date your return tickets booked to?
Ans - 20th May 2017
I: Hopefully this will be done by this date. We will contact you via email and ask you to submit your passport if no other documents are requested.
Note: After this she returned back our passports and we came back.

Today is 25th May, I am everyday checking emails and still hoping that I will hear back soon from them. But till date no luck. My office folks have given me deadline that if we dont hear back from USCIS by 30th May then we will send other person. Is there anyone experience/or experienced similar case?
I know it's unknown but I am really wondering how long Administrative Processing will take when they have not requested any additional document.