It's highly unlikely that NS is using a statewide public safety radio system for regular operations. That would require a wholesale change-out of radio equipment in dispatch centers, yard offices, lineside remote bases, lineside defect detectors, locomotives, mobile track equipment, track inspector and signal maintainer vehicles, and handheld radios carried by conductors, brakemen, road foremen, etc. It's more likely that they have moved to a different frequency in the railroad VHF band which is roughly 160.0 to 161.6 MHz. It is also possible that they have moved to NXDN digital voice on an existing railroad frequency, but that's usually only in localized areas.