This is a notice of availability and request for public comment on a non-NEPA regulatory action. The Northeast Illinois Regional Corporation (NIRC) submitted a request for amendment (RFA) on February 24, 2026, to its FRA-certified Interoperable Electronic Train Management System positive train control (PTC) system. The RFA seeks FRA approval for two planned PTC system outages to support required network maintenance and firewall hardware upgrades. FRA published this notice under 49 CFR 236.1021(e) because the RFA constitutes a material modification of a train control system. The public comment period closes March 26, 2026.1