How long (approximate time) should an alient wait after our employer sends a petition for H1-B (U.S. immigrant successfully approves our employer's petition) ?
I was told by my attorney that I can start working when the EAC number is received. But I would suggest you contact either your employer's attorney or an immigration lawyer.
3-6 months. Once you get the case number, you can look up on the Service Center's website to look at the progress. Premium processing (additional $1000) is done in a week-15 days. Hope that helps! Amit