Advancing Nuclear Regulatory Oversight Act This bill requires the Nuclear Regulatory Commission to report to Congress about (1) changes to its regulation of nuclear reactors and materials during the COVID-19 public health emergency, and (2) actions (e.g., the use of risk-informed, performance-based procedures) that may be implemented to enhance the efficiency of oversight and inspection programs. Additionally, the Government Accountability Office must conduct a review of the commission's office and other facility space requirements and recommend ways to reduce office and facility costs.