The IRS is stating that it will take about 9 weeks to complete the processing of the return once you have verified your identity. You can also find that information here Understand Your 4883C Letter
If it's after 9 weeks and you don't hear anything, I'd recommend you call them at the IRS tax refund hotline at 800-829-4477, Monday - Friday, 7:00 a.m. to 11:30 p.m. Or, call the 24-hour assistance number at 800-829-1040.
