Your wife needs to be careful here. It appears that she was out of status at the time that the application for extension of status was filed. If your employer explained to the USCIS that the mistake was theirs they may be inclined to forgive the gap. However, your wife is presently out of status and unlawfully present. If you don't get an answer from the USCIS within 180 days from the date her status expired she should leave or will face a 3 year bar on re-entry. This becomes a 10 year bar if she is unlawfully present for 1 year or more from the date her status expired. You should definitely calendar the 180 day period very carefully and hope that you get a response before then.