How many days does it take to receive the offer letter from EY GDS?

Hello Everyone,

I have completed three interview rounds: Technical, Managerial, and Onshore in EY GDS. All of them went well. Last Thursday, July 17th, the HR representative called to inform me that I passed all rounds and asked about my expectations. He mentioned that he would check with the hiring manager and others, and then he will let me know the next steps. Do you have any idea how long this process might take and what the next steps could be? Since a week has already passed.