Inquiry Tier System:
The following information regarding the USCIS "800 number" customer service line, which is now the exclusive means of telephone contact with respect to non-premium processing cases filed at Service Centers, has been gleaned from several sources within the USCIS:

1. The 800 number feeds into two offices, and incoming calls may be routed to either. There are two tiers of people staffing the calls. Tier 1 responds from scripts and is staffed by contractors who are largely clerical type personnel. They should not be expected to be familiar with immigration terminology or concepts. If the question cannot be handled at Tier 1, the call is forwarded to Tier 2.
2. Tier 2 handles more complex issues and officers have received training similar to present service center Information Officers. However, Tier 2 personnel may very well have no prior experience with service center processing or operations. If the Tier 2 operator is unable to resolve the question, they refer the question to the appropriate Service Center and the Service Center has 14 to 30 days to respond in writing. If there is no response received within 30 days, a call should be made back to the Customer Service Center and an "exception broker" can call the Service Center for an answer.