How much does TCS take to release an offer letter?

I had given an interview in TCS and got a mail on 12th Aug stating that I have cleared both Technical and Managerial rounds. I have uploaded all the documents on ibegin portal.

Also, on 16th Aug I got a call from HR stating that my BGV has been done and they will release the offer in 1-2 weeks.

Can someone please let me know how much time it takes to release an offer letter.